├── index.js ├── src ├── test.js ├── pTableUnits.js └── pTableProperties.js ├── package.json ├── LICENSE └── README.md /index.js: -------------------------------------------------------------------------------- 1 | /* The definitive data-set for chemical elements */ 2 | /* Collator: Scott Weaver @sweaver2112 */ 3 | /* Data collated from many public sources, including those listed below */ 4 | /* https://github.com/Bowserinator/Periodic-Table-JSON */ 5 | /* wikipedia.com */ 6 | /* ptable.com */ 7 | /* periodictable.com */ 8 | 9 | import { pTable } from "./src/pTable.js"; 10 | import { pTableUnits } from "./src/pTableUnits.js"; 11 | import { pTableProperties } from "./src/pTableProperties.js"; 12 | 13 | export { pTable } 14 | export { pTableUnits } 15 | export { pTableProperties } -------------------------------------------------------------------------------- /src/test.js: -------------------------------------------------------------------------------- 1 | import {pTable, pTableUnits, pTableProperties} from '../index.js'; 2 | 3 | var pt = JSON.parse(pTable) 4 | var units = JSON.parse(pTableUnits) 5 | var props = JSON.parse(pTableProperties) 6 | console.log(`>Props (abundance):${props.abundance}\n>Second element universal abundance:${pt[1].abundance.universe}${units.abundance.universe } }`) 7 | 8 | console.log("----------Table----------"); 9 | console.log(pTable); 10 | console.log("----------Props----------"); 11 | console.log(pTableProperties); 12 | console.log("----------Units----------"); 13 | console.log(pTableUnits); -------------------------------------------------------------------------------- /package.json: -------------------------------------------------------------------------------- 1 | { 2 | "name": "periodic-table-data-complete", 3 | "version": "1.0.0", 4 | "description": "The definitive dataset for chemical elements.", 5 | "main": "index.js", 6 | "type": "module", 7 | "scripts": { 8 | "test": "echo \"Error: no test specified\" && exit 1" 9 | }, 10 | "repository": { 11 | "type": "git", 12 | "url": "git+https://github.com/sweaver2112/periodic-table-data-complete.git" 13 | }, 14 | "keywords": [ 15 | "periodic-table", 16 | "chemical-elements", 17 | "chemistry", 18 | "data", 19 | "json" 20 | ], 21 | "author": "Scott Weaver", 22 | "license": "MIT", 23 | "bugs": { 24 | "url": "https://github.com/sweaver2112/periodic-table-data-complete/issues" 25 | }, 26 | "homepage": "https://github.com/sweaver2112/periodic-table-data-complete#readme" 27 | } 28 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | MIT License 2 | 3 | Copyright (c) 2025 Scott Weaver 4 | 5 | Permission is hereby granted, free of charge, to any person obtaining a copy 6 | of this software and associated documentation files (the "Software"), to deal 7 | in the Software without restriction, including without limitation the rights 8 | to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 9 | copies of the Software, and to permit persons to whom the Software is 10 | furnished to do so, subject to the following conditions: 11 | 12 | The above copyright notice and this permission notice shall be included in all 13 | copies or substantial portions of the Software. 14 | 15 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 | IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 | FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 18 | AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 | LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 20 | OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 21 | SOFTWARE. 22 | -------------------------------------------------------------------------------- /src/pTableUnits.js: -------------------------------------------------------------------------------- 1 | /* Author:Scott Weaver https://github.com/sweaver2112/periodic-table-data-complete */ 2 | const pTableUnits = JSON.stringify( 3 | 4 | { 5 | "abundance": { 6 | "universe": "%", 7 | "solar": "%", 8 | "meteor": "%", 9 | "crust": "%", 10 | "human": "%" 11 | }, 12 | "atomic_mass": "amu", 13 | "boiling_point": { 14 | "celsius": "°", 15 | "fahrenheit": "°", 16 | "kelvin": "K" 17 | }, 18 | "conductivity": { 19 | "thermal": "W/mK", 20 | "electric": "MS/m" 21 | }, 22 | "curie_point": "K", 23 | "density": { 24 | "shear": "GPa", 25 | "young": "GPa", 26 | "stp": "kg/m³", 27 | "liquid": "kg/m³" 28 | }, 29 | "discovered": "year", 30 | "electron_affinity": "kJ/mol", 31 | "electronegativity_pauling": "kJ/mol", 32 | "energy_levels": "e⁻️", 33 | "half_life": "year", 34 | "hardness": { 35 | "radius": "pm", 36 | "vickers": "MPa", 37 | "brinell": "MPa", 38 | "mohs": "MPa" 39 | }, 40 | "heat": { 41 | "specific": "J/(kg K)", 42 | "fusion": "kJ/mol", 43 | "vaporization": "kJ/mol", 44 | "molar": "J/K.mol" 45 | }, 46 | "ionization_energies": "kJ/mol", 47 | "lattice_constants": "pm", 48 | "lifetime": "year", 49 | "magnetic_susceptibility": { 50 | "mass": "m³/Kg", 51 | "molar": "m³/mol" 52 | }, 53 | "melting_point": { 54 | "celsius": "°", 55 | "fahrenheit": "°", 56 | "kelvin": "K" 57 | }, 58 | "modulus": { 59 | "bulk": "GPa" 60 | }, 61 | "neel_point": "K", 62 | "radius": { 63 | "calculated": "pm", 64 | "empirical": "pm", 65 | "covalent": "pm", 66 | "vanderwaals": "pm" 67 | }, 68 | "resistivity": "m Ω", 69 | "speed_of_sound": "m/s", 70 | "superconducting_point": "K", 71 | "thermal_expansion": "K⁻¹" 72 | }); 73 | 74 | export { pTableUnits } -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # periodic-table-data-complete 2 | 3 | -- powering http://ChemStudent.net -- 4 | 5 | The definitive dataset for chemical elements. 6 | 7 | Collator: Scott Weaver @sweaver2112 8 | 9 | ### acknowledgements 10 | 11 | https://github.com/Bowserinator/Periodic-Table-JSON, 12 | 13 | http://en.wikipedia.com, 14 | 15 | http://pTable.com, 16 | 17 | http://periodictable.com 18 | 19 | https://www.convertonline.io/convert/js-to-json 20 | 21 | ## Notes 22 | 23 | 1. The data is not flat - compound values are objects (Hardness, Abundance, Heat Of, Melting Point, Boiling Point, and many more) 24 | 2. Summary includes entire Wikipedia first section, consequently it retains the paragraph tags from the source: <p>summary text...</p><p>next paragraph...</p> 25 | 3. Isomorphic units map is included (it has the same structure and names as the pTable) 26 | 4. Property definitions (such as: melting_point) are included as HTML with link to Wikipedia article 27 | 28 | ## Installation 29 | 30 | `npm install periodic-table-data-complete` 31 | 32 | (raw JSON and CSV files are also provided) 33 | 34 | ## Usage 35 | 36 | as an npm package: 37 | 38 | ```javascript 39 | import { pTable, pTableUnits, pTableProperties } from periodic-table-data-complete` 40 | ``` 41 | 42 | using the source directly: 43 | 44 | ```HTML 45 | 50 | ``` 51 | 52 | The PTable is an array of objects, each object representing one chemical element. 53 | 54 | Thus, to find, for example, the universal abundance of Helium (noting that Helium is the 2nd element by atomic number) : 55 | 56 | ```javascript 57 | var pt = JSON.parse(pTable) 58 | pt[1].abundance.universe => 23 59 | ``` 60 | more likely, you'll want to fetch an element by symbol: 61 | 62 | ```javascript 63 | pt.find(el=>el.symbol=="B") => Boron object 64 | ``` 65 | 66 | ### Units 67 | 68 | ```javascript 69 | var units = JSON.parse(pTableUnits) 70 | units.abundance.universe => "%" 71 | ``` 72 | 73 | ### Property Defintions 74 | 75 | ```javascript 76 | var chemical_properties = JSON.parse(pTableProperties) 77 | chemical_properties.atomic_number => 'The atomic number or proton number (symbol Z) of a chemical element is the number of protons found in the nucleus of every atom of that element. The atomic number uniquely identifies a chemical element. It is identical to the charge number of the nucleus. In an uncharged atom, the atomic number is also equal to the number of electrons.' 78 | ``` 79 | 80 | ## Hierarchy / Available Properties 81 | 82 | abundance.crust,
abundance.human,
abundance.meteor,
abundance.ocean,
abundance.solar,
abundance.universe,
adiabatic_index,
allotropes,
alternate_names,
appearance,
atomic_mass,
atomic_number,
block,
boiling_point,
classifications.cas_number,
classifications.cid_number,
classifications.dot_hazard_class,
classifications.dot_numbers,
classifications.rtecs_number,
conductivity.electric,
conductivity.thermal,
cpk_hex,
critical_pressure,
critical_temperature,
crystal_structure,
curie_point,
decay_mode,
density.liquid,
density.stp,
discovered.by,
discovered.location,
discovered.year,
electrical_type,
electron_affinity,
electron_configuration,
electron_configuration_semantic,
electronegativity_pauling,
electrons_per_shell.0,
electrons_per_shell.1,
electrons_per_shell.2,
electrons_per_shell.3,
electrons_per_shell.4,
electrons_per_shell.5,
electrons_per_shell.6,
electrons_per_shell.7,
energy_levels,
gas_phase,
group,
half-life,
hardness.brinell,
hardness.mohs,
hardness.vickers,
heat.fusion,
heat.molar,
heat.specific,
heat.vaporization,
ionization_energies.0,
ionization_energies.1,
ionization_energies.2,
ionization_energies.3,
ionization_energies.4,
ionization_energies.5,
ionization_energies.6,
ionization_energies.7,
ionization_energies.8,
ionization_energies.9,
ionization_energies.10,
ionization_energies.11,
ionization_energies.12,
ionization_energies.13,
ionization_energies.14,
ionization_energies.15,
ionization_energies.16,
ionization_energies.17,
ionization_energies.18,
ionization_energies.19,
ionization_energies.20,
ionization_energies.21,
ionization_energies.22,
ionization_energies.23,
ionization_energies.24,
ionization_energies.25,
ionization_energies.26,
ionization_energies.27,
ionization_energies.28,
ionization_energies.29,
isotopes_known,
isotopes_stable,
isotopic_abundances,
lattice_angles,
lattice_constants,
lifetime,
magnetic_susceptibility.mass,
magnetic_susceptibility.molar,
magnetic_susceptibility.volume,
magnetic_type,
melting_point,
modulus.bulk,
modulus.shear,
modulus.young,
molar_volume,
name,
neel_point,
neutron_cross_section,
neutron_mass_absorption,
oxidation_states,
period,
phase,
poisson_ratio,
quantum_numbers,
radius.calculated,
radius.covalent,
radius.empirical,
radius.vanderwaals,
refractive_index,
resistivity,
series,
source,
space_group_name,
space_group_number,
speed_of_sound,
summary,
superconducting_point,
symbol,
thermal_expansion,
valence_electrons 83 | 84 | 85 | -------------------------------------------------------------------------------- /src/pTableProperties.js: -------------------------------------------------------------------------------- 1 | /* Author:Scott Weaver https://github.com/sweaver2112/periodic-table-data-complete */ 2 | const pTableProperties = JSON.stringify({ 3 | abundance : `The abundance of the chemical elements is a measure of the occurrence of the chemical elements relative to all other elements in a given environment. Abundance is measured in one of three ways: by the mass-fraction (the same as weight fraction); by the mole-fraction (fraction of atoms by numerical count, or sometimes fraction of molecules in gases); or by the volume-fraction. Volume-fraction is a common abundance measure in mixed gases such as planetary atmospheres, and is similar in value to molecular mole-fraction for gas mixtures at relatively low densities and pressures, and ideal gas mixtures.`, 4 | adiabatic_index: `The heat capacity ratio, also known as the adiabatic index, the ratio of specific heats, or Laplace's coefficient, is the ratio of the heat capacity at constant pressure to heat capacity at constant volume. It is sometimes also known as the isentropic expansion factor and is denoted by γ (gamma) for an ideal gas[note 1] or κ (kappa), the isentropic exponent for a real gas. The symbol γ is used by aerospace and chemical engineers.`, 5 | allotropes: `Allotropy or allotropism (from Ancient Greek ἄλλος (allos) 'other', and τρόπος (tropos) 'manner, form') is the property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes of the elements. Allotropes are different structural modifications of an element: the atoms of the element are bonded together in a different manner. For example, the allotropes of carbon include diamond (the carbon atoms are bonded together to form a cubic lattice of tetrahedra), graphite (the carbon atoms are bonded together in sheets of a hexagonal lattice), graphene (single sheets of graphite), and fullerenes (the carbon atoms are bonded together in spherical, tubular, or ellipsoidal formations).`, 6 | atomic_mass:`The atomic mass (ma or m) is the mass of an atom. Although the SI unit of mass is the kilogram (symbol: kg), atomic mass is often expressed in the non-SI unit atomic mass unit (amu) or unified mass (u) or dalton (symbol: Da), where 1amu = 1u = 1Da = 1⁄12 of the mass of a single carbon-12 atom, at rest. The protons and neutrons of the nucleus account for nearly all of the total mass of atoms, with the electrons and nuclear binding energy making minor contributions. Thus, the numeric value of the atomic mass when expressed in daltons has nearly the same value as the mass number.`, 7 | atomic_number:`The atomic number or proton number (symbol Z) of a chemical element is the number of protons found in the nucleus of every atom of that element. The atomic number uniquely identifies a chemical element. It is identical to the charge number of the nucleus. In an uncharged atom, the atomic number is also equal to the number of electrons.`, 8 | block:`A block of the periodic table is a set of elements unified by the atomic orbitals their valence electrons or vacancies lie in. The term appears to have been first used by Charles Janet. Each block is named after its characteristic orbital: s-block, p-block, d-block, and f-block.`, 9 | boiling_point:`The boiling point of a substance is the temperature at which the vapor pressure of a liquid equals the pressure surrounding the liquid and the liquid changes into a vapor.`, 10 | classifications_cas_number:`A CAS Registry Number, also referred to as CAS RN or informally CAS Number, is a unique numerical identifier assigned by the Chemical Abstracts Service (CAS), US to every chemical substance described in the open scientific literature. It includes all substances described from 1957 through the present, plus some substances from as far back as the early 1800s. It includes organic and inorganic compounds, minerals, isotopes, alloys, mixtures, and nonstructurable materials (UVCBs, substances of unknown or variable composition, complex reaction products, or biological origin). CAS RNs are generally serial numbers (with a check digit), so they do not contain any information about the structures themselves the way SMILES and InChI strings do.`, 11 | classifications_cid_number:`Compound Identification Number in PubChem, a database of chemical molecules and their activities against biological assays. The system is maintained by the National Center for Biotechnology Information (NCBI), a component of the National Library of Medicine, which is part of the United States National Institutes of Health (NIH). PubChem can be accessed for free through a web user interface. PubChem contains multiple substance descriptions and small molecules with fewer than 100 atoms and 1000 bonds.`, 12 | classifications_dot_hazard_class:`The hazard class of dangerous goods/commodities is indicated either by its class (or division) number or name. Placards are used to identify the class or division of a material. The hazard class or division number must be displayed in the lower corner of a placard and is required for both primary and subsidiary hazard classes and divisions, if applicable.`, 13 | classifications_dot_numbers:`An UN number (United Nations number) is a four-digit number that identifies hazardous materials, and articles (such as explosives, flammable liquids, oxidizers, toxic liquids, etc.) in the framework of international transport. Some hazardous substances have their own UN numbers (e.g. acrylamide has UN 2074), while sometimes groups of chemicals or products with similar properties receive a common UN number (e.g. flammable liquids, not otherwise specified, have UN 1993). A chemical in its solid state may receive a different UN number than the liquid phase if their hazardous properties differ significantly; substances with different levels of purity (or concentration in solution) may also receive different UN numbers.`, 14 | classifications_rtecs_number:`Registry of Toxic Effects of Chemical Substances (RTECS) is a database of toxicity information compiled from the open scientific literature without reference to the validity or usefulness of the studies reported. Until 2001 it was maintained by US National Institute for Occupational Safety and Health (NIOSH) as a freely available publication. It is now maintained by a private company.`, 15 | conductivity_electric:`Electrical conductivity or specific conductance is the reciprocal of electrical resistivity. It represents a material's ability to conduct electric current. It is commonly signified by the Greek letter σ (sigma), but κ (kappa) (especially in electrical engineering) and γ (gamma) are sometimes used. The SI unit of electrical conductivity is siemens per metre (S/m) with values given in Megasiemens per metre (MS/m).`, 16 | conductivity_thermal:`The thermal conductivity of a material is a measure of its ability to conduct heat. It is commonly denoted by k or λ. Heat transfer occurs at a lower rate in materials of low thermal conductivity than in materials of high thermal conductivity. For instance, metals typically have high thermal conductivity and are very efficient at conducting heat, while the opposite is true for insulating materials like Styrofoam. Correspondingly, materials of high thermal conductivity are widely used in heat sink applications, and materials of low thermal conductivity are used as thermal insulation. The reciprocal of thermal conductivity is called thermal resistivity.`, 17 | cpk_hex:`The CPK coloring scheme is a popular color convention for distinguishing atoms of different chemical elements in molecular models, originating out of Caltech in 1952.`, 18 | critical_pressure:`The critical pressure of a substance is the pressure required to liquefy a gas at its critical temperature. In thermodynamics, a critical point (or critical state) is the end point of a phase equilibrium curve. The most prominent example is the liquid-vapor critical point, the end point of the pressure-temperature curve that designates conditions under which a liquid and its vapor can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a critical temperature Tc and a critical pressure Pc, phase boundaries vanish. Other examples include the liquid-liquid critical points in mixtures, and the ferromagnet-paramagnet transition in the absence of an external magnetic field.`, 19 | critical_temperature:`The critical temperature of a substance is the temperature at and above which vapor of the substance cannot be liquefied, no matter how much pressure is applied. Every substance has a critical temperature. In thermodynamics, a critical point (or critical state) is the end point of a phase equilibrium curve. The most prominent example is the liquid-vapor critical point, the end point of the pressure-temperature curve that designates conditions under which a liquid and its vapor can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a critical temperature Tc and a critical pressure Pc, phase boundaries vanish. Other examples include the liquid-liquid critical points in mixtures, and the ferromagnet-paramagnet transition in the absence of an external magnetic field.`, 20 | crystal_structure:`Crystal structure is a description of the ordered arrangement of atoms, ions or molecules in a crystalline material. Ordered structures occur from the intrinsic nature of the constituent particles to form symmetric patterns that repeat along the principal directions of three-dimensional space in matter. The smallest group of particles in the material that constitutes this repeating pattern is the unit cell of the structure. The unit cell completely reflects the symmetry and structure of the entire crystal, which is built up by repetitive translation of the unit cell along its principal axes.`, 21 | curie_point:`The Curie temperature, or Curie point, is the temperature above which certain materials lose their permanent magnetic properties, which can (in most cases) be replaced by induced magnetism. The Curie temperature is named after Pierre Curie, who showed that magnetism was lost at a critical temperature. The force of magnetism is determined by the magnetic moment, a dipole moment within an atom which originates from the angular momentum and spin of electrons. Materials have different structures of intrinsic magnetic moments that depend on temperature; the Curie temperature is the critical point at which a material's intrinsic magnetic moments change direction.`, 22 | decay_mode:`Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered radioactive. Three of the most common types of decay are alpha decay (α-decay), beta decay (β-decay), and gamma decay (γ-decay), all of which involve emitting one or more particles. The weak force is the mechanism that is responsible for beta decay, while the other two are governed by the electromagnetic and strong forces. Radioactive decay is a stochastic (i.e. random) process at the level of single atoms. According to quantum theory, it is impossible to predict when a particular atom will decay, regardless of how long the atom has existed. However, for a significant number of identical atoms, the overall decay rate can be expressed as a decay constant or as half-life. The half-lives of radioactive atoms have a huge range; from nearly instantaneous to far longer than the age of the universe.`, 23 | density:`The density (more precisely, the volumetric mass density; also known as specific mass), of a substance is its mass per unit volume. The symbol most often used for density is ρ (the lower case Greek letter rho), although the Latin letter D can also be used. Mathematically, density is defined as mass divided by volume: ρ = M / V, where ρ is the density, m is the mass, and V is the volume. In some cases (for instance, in the United States oil and gas industry), density is loosely defined as its weight per unit volume, although this is scientifically inaccurate – this quantity is more specifically called specific weight. Osmium and iridium are the densest known elements at standard conditions for temperature and pressure.`, 24 | electrical_type:` A categorization of how well an element conducts electricity (conductivity/resistivity). Since most elements are metals, most conduct electricity well and are conductors, with some metalloids and non-metals being semiconductors or insulators.`, 25 | electron_affinity:`The electron affinity of an atom or molecule is defined as the amount of energy released when an electron is attached to a neutral atom or molecule in the gaseous state to form an anion. X(g) + e⁻️ → X⁻️(g) + energy. Note that this is not the same as the enthalpy change of electron capture ionization, which is defined as negative when energy is released. In other words, the enthalpy change and the electron affinity differ by a negative sign.`, 26 | electron_configuration:`The electron configuration is the distribution of electrons of an atom or molecule (or other physical structure) in atomic or molecular orbitals. For example, the electron configuration of the neon atom is 1s2 2s2 2p6, meaning that the 1s, 2s and 2p subshells are occupied by 2, 2 and 6 electrons respectively. Electronic configurations describe each electron as moving independently in an orbital, in an average field created by all other orbitals. Mathematically, configurations are described by Slater determinants or configuration state functions.`, 27 | electron_configuration_semantic:`The noble gas configuration is a shorthand method of writing an atom’s electron configuration. The reason for using the noble gas configuration is because the full electron configuration becomes very long for atoms with high atomic numbers. With noble gas configuration, the electron configuration starts with the symbol of the noble gas in the previous period, followed by the additional configuration of the electrons for the given element.`, 28 | electronegativity_pauling:`Electronegativity, symbolized as χ, is the tendency for an atom of a given chemical element to attract shared electrons (or electron density) when forming a chemical bond. An atom's electronegativity is affected by both its atomic number and the distance at which its valence electrons reside from the charged nucleus. The higher the associated electronegativity, the more an atom or a substituent group attracts electrons. Electronegativity serves as a simple way to quantitatively estimate the bond energy, and the sign and magnitude of a bond's chemical polarity, which characterizes a bond along the continuous scale from covalent to ionic bonding. The loosely defined term electropositivity is the opposite of electronegativity: it characterizes an element's tendency to donate valence electrons.`, 29 | electrons_per_shell:`An electron shell may be thought of as an orbit followed by electrons around an atom's nucleus. The closest shell to the nucleus is called the "1 shell" (also called the "K shell"), followed by the "2 shell" (or "L shell"), then the "3 shell" (or "M shell"), and so on farther and farther from the nucleus. The shells correspond to the principal quantum numbers (n = 1, 2, 3, 4 ...) or are labeled alphabetically with the letters used in X-ray notation (K, L, M, …). Each shell can contain only a fixed number of electrons: The first shell can hold up to two electrons, the second shell can hold up to eight (2 + 6) electrons, the third shell can hold up to 18 (2 + 6 + 10) and so on. The general formula is that the nth shell can in principle hold up to 2(n^2) electrons.`, 30 | energy_levels:`A quantum mechanical system or particle that is bound—that is, confined spatially—can only take on certain discrete values of energy, called energy levels. This contrasts with classical particles, which can have any amount of energy. The term is commonly used for the energy levels of the electrons in atoms, ions, or molecules, which are bound by the electric field of the nucleus, but can also refer to energy levels of nuclei or vibrational or rotational energy levels in molecules. The energy spectrum of a system with such discrete energy levels is said to be quantized.`, 31 | gas_phase:`Atomicity is defined as the total number of atoms present in a molecule. For example, each molecule of oxygen (O2) is composed of two oxygen atoms. So atomicity of oxygen is 2. In older contexts, atomicity is sometimes used in the same sense as valency. Some authors also use the term to refer to the maximum number of valencies observed for an element. On the basis of atomicity, molecules can be classified as Monotomic (one atom), Diatomic (two atoms), Triatomic (3 atoms), or Polyatomic (3 or more atoms). All metals and some other elements, such as carbon, do not have a simple structure but consist of a very large and indefinie number of atoms bonded together. Their atomicity cannot be determined and is usually considered as 1. Atomicity may vary in different allotropes of the same element.`, 32 | group:`A group (also known as a family) is a column of elements in the periodic table of the chemical elements. There are 18 numbered groups in the periodic table; the f-block columns (between groups 2 and 3) are not numbered. The elements in a group have similar physical or chemical characteristics of the outermost electron shells of their atoms (i.e., the same core charge), because most chemical properties are dominated by the orbital location of the outermost electron.`, 33 | half_life:`Half-life is the time required for a quantity to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable atoms survive. The term is also used more generally to characterize any type of exponential or non-exponential decay. For example, the medical sciences refer to the biological half-life of drugs and other chemicals in the human body. The converse of half-life is doubling time. The original term, half-life period, dating to Ernest Rutherford's discovery of the principle in 1907, was shortened to half-life in the early 1950s. Rutherford applied the principle of a radioactive element's half-life to studies of age determination of rocks by measuring the decay period of radium to lead-206.`, 34 | hardness_brinell:`The Brinell scale characterizes the indentation hardness of materials through the scale of penetration of an indenter, loaded on a material test-piece. It is one of several definitions of hardness in materials science. Proposed by Swedish engineer Johan August Brinell in 1900, it was the first widely used and standardised hardness test in engineering and metallurgy. The large size of indentation and possible damage to test-piece limits its usefulness. However, it also had the useful feature that the hardness value divided by two gave the approximate UTS in ksi for steels. This feature contributed to its early adoption over competing hardness tests.`, 35 | hardness_mohs:`The Mohs scale of mineral hardness (/moʊz/) is a qualitative ordinal scale, from 1 to 10, characterizing scratch resistance of various minerals through the ability of harder material to scratch softer material. The scale was introduced in 1822 by German geologist and mineralogist Friedrich Mohs, in his Treatise on Mineralogy; it is one of several definitions of hardness in materials science, some of which are more quantitative. The method of comparing hardness by observing which minerals can scratch others is of great antiquity, having been mentioned by Theophrastus in his treatise On Stones, c. 300 BC, followed by Pliny the Elder in his Naturalis Historia, c. AD 77. The Mohs scale is useful for identification of minerals in the field, but is not an accurate predictor of how well materials endure in an industrial setting - toughness.`, 36 | hardness_vickers:`The Vickers hardness test was developed in 1921 by Robert L. Smith and George E. Sandland at Vickers Ltd as an alternative to the Brinell method to measure the hardness of materials. The Vickers test is often easier to use than other hardness tests since the required calculations are independent of the size of the indenter, and the indenter can be used for all materials irrespective of hardness. The basic principle, as with all common measures of hardness, is to observe a material's ability to resist plastic deformation from a standard source. The Vickers test can be used for all metals and has one of the widest scales among hardness tests. The unit of hardness given by the test is known as the Vickers Pyramid Number or Diamond Pyramid Hardness (DPH). The hardness number can be converted into units of pascals, but should not be confused with pressure, which uses the same units.`, 37 | heat_fusion:`The enthalpy of fusion of a substance, also known as (latent) heat of fusion is the change in its enthalpy resulting from providing energy, typically heat, to a specific quantity of the substance to change its state from a solid to a liquid, at constant pressure. For example, when melting 1 kg of ice (at 0 °C under a wide range of pressures), 333.55 kJ of energy is absorbed with no temperature change. The heat of solidification (when a substance changes from liquid to solid) is equal and opposite.`, 38 | heat_molar:`The molar heat capacity of a chemical substance is the amount of energy that must be added, in the form of heat, to one mole of the substance in order to cause an increase of one unit in its temperature. Alternatively, it is the heat capacity of a sample of the substance divided by the amount of substance of the sample; or also the specific heat capacity of the substance times its molar mass. The SI unit of specific heat is joule per kelvin per mole, J⋅K⁻️1⋅mol⁻️1. Like the specific heat, measured the molar heat capacity of a substance, especially a gas, may be significantly higher when the sample is allowed to expand as it is heated (at constant pressure, or isobaric) than when is heated in a closed vessel that prevents expansion (at constant volume, or isochoric). The ratio between the two, however, is the same heat capacity ratio obtained from the corresponding specific heat capacities.`, 39 | heat_specific:`The specific heat capacity (symbol cp) of a substance is the heat capacity of a sample of the substance divided by the mass of the sample. Specific heat is also sometimes referred to as massic heat capacity. Informally, it is the amount of heat that must be added to one unit of mass of the substance in order to cause an increase of one unit in temperature. The SI unit of specific heat capacity is joule per kelvin per kilogram, J⋅kg⁻️1⋅K⁻️1. For example, the heat required to raise the temperature of 1 kg of water by 1 K is 4184 joules, so the specific heat capacity of water is 4184 J⋅kg⁻️1⋅K⁻️1.`, 40 | heat_vaporization:`The enthalpy of vaporization (symbol ∆H), also known as the (latent) heat of vaporization or heat of evaporation, is the amount of energy (enthalpy) that must be added to a liquid substance to transform a quantity of that substance into a gas. The enthalpy of vaporization is a function of the pressure at which that transformation takes place. The enthalpy of vaporization is often quoted for the normal boiling temperature of the substance. Although tabulated values are usually corrected to 298 K, that correction is often smaller than the uncertainty in the measured value.`, 41 | ionization_energies:`Ionization energy is the minimum energy required to remove the most loosely bound electron of an isolated neutral gaseous atom or molecule. It is quantitatively expressed as X(g) + energy ⟶ X+(g) + e⁻️, where X is any atom or molecule, X+ is the resultant ion when the original atom was stripped of a single electron, and e⁻️ is the removed electron.`, 42 | isotopes_known:`Isotopes are two or more types of atoms that have the same atomic number (number of protons in their nuclei) and position in the periodic table (and hence belong to the same chemical element), and that differ in nucleon numbers (mass numbers) due to different numbers of neutrons in their nuclei. While all isotopes of a given element have almost the same chemical properties, they have different atomic masses and physical properties. The term isotope is formed from the Greek roots isos (ἴσος "equal") and topos (τόπος "place"), meaning "the same place"; thus, the meaning behind the name is that different isotopes of a single element occupy the same position on the periodic table. It was coined by Scottish doctor and writer Margaret Todd in 1913 in a suggestion to chemist Frederick Soddy.`, 43 | isotopes_stable:`Stable nuclides are nuclides that are not radioactive and so (unlike radionuclides) do not spontaneously undergo radioactive decay. When such nuclides are referred to in relation to specific elements, they are usually termed stable isotopes.`, 44 | isotopic_abundances:`Natural abundance refers to the abundance of isotopes of a chemical element as naturally found on a planet. The relative atomic mass (a weighted average, weighted by mole-fraction abundance figures) of these isotopes is the atomic weight listed for the element in the periodic table. The abundance of an isotope varies from planet to planet, and even from place to place on the Earth, but remains relatively constant in time (on a short-term scale).`, 45 | lattice_angles:`A lattice constant or lattice parameter is one of the physical dimensions and angles that determine the geometry of the unit cells in a crystal lattice. Lattices in three dimensions generally have six lattice constants: the lengths a, b, and c of the three cell edges meeting at a vertex, and the angles α, β, and γ between those edges. The crystal lattice parameters a, b, and c have the dimension of length. Their SI unit is the meter, and they are traditionally specified in angstroms (Å); an angstrom being 0.1 nanometer (nm), or 100 picometres (pm). Typical values start at a few angstroms. The angles α, β, and γ are usually specified in degrees.`, 46 | lattice_constants:`A lattice constant or lattice parameter is one of the physical dimensions and angles that determine the geometry of the unit cells in a crystal lattice. Lattices in three dimensions generally have six lattice constants: the lengths a, b, and c of the three cell edges meeting at a vertex, and the angles α, β, and γ between those edges. The crystal lattice parameters a, b, and c have the dimension of length. Their SI unit is the meter, and they are traditionally specified in angstroms (Å); an angstrom being 0.1 nanometer (nm), or 100 picometres (pm). Typical values start at a few angstroms. The angles α, β, and γ are usually specified in degrees.`, 47 | lifetime:`The summation of the life of each radioactive atom divided by the initial number of atoms is called the mean or average life of that radioactive substance. This time interval may be thought of as the sum of the lifetimes of all the individual unstable nuclei in a sample, divided by the total number of unstable nuclei present.`, 48 | magnetic_susceptibility:`The magnetic susceptibility (Latin: susceptibilis, "receptive"; denoted χ) is a measure of how much a material will become magnetized in an applied magnetic field. It is the ratio of magnetization M (magnetic moment per unit volume) to the applied magnetizing field intensity H.`, 49 | magnetic_type:`When an isolated atom is placed in a magnetic field there is an interaction because each electron in the atom behaves like a magnet, that is, the electron has a magnetic moment. There are two types of magnetic interaction. Diamagnetism: When placed in a magnetic field the atom becomes magnetically polarized, that is, it develops an induced magnetic moment. The force of the interaction tends to push the atom out of the magnetic field. Very frequently diamagnetic atoms have no unpaired electrons ie each electron is paired with another electron in the same atomic orbital. The moments of the two electrons cancel each other out, so the atom has no net magnetic moment. However, for the ion Eu3+ which has six unpaired electrons, the orbital angular momentum cancels out the electron angular momentum, and this ion is diamagnetic at zero Kelvin. Paramagnetism: At least one electron is not paired with another. The atom has a permanent magnetic moment. When placed into a magnetic field, the atom is attracted into the field. In certain crystalline materials individual magnetic moments may be aligned with each other (magnetic moment has both magnitude and direction). This gives rise to ferromagnetism, antiferromagnetism or ferrimagnetism. These are properties of the crystal as a whole, of little bearing on chemical properties.`, 50 | melting_point:`The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends on pressure and is usually specified at a standard pressure such as 1 atmosphere or 100 kPa. When considered as the temperature of the reverse change from liquid to solid, it is referred to as the freezing point or crystallization point. Because of the ability of substances to supercool, the freezing point can easily appear to be below its actual value. When the "characteristic freezing point" of a substance is determined, in fact, the actual methodology is almost always "the principle of observing the disappearance rather than the formation of ice, that is, the melting point."`, 51 | modulus_bulk:`The bulk modulus (K or B) of a substance is a measure of how resistant to compression that substance is. It is defined as the ratio of the infinitesimal pressure increase to the resulting relative decrease of the volume. Other moduli describe the material's response (strain) to other kinds of stress: the shear modulus describes the response to shear stress, and Young's modulus describes the response to normal stress. For a fluid, only the bulk modulus is meaningful. For a complex anisotropic solid such as wood or paper, these three moduli do not contain enough information to describe its behaviour, and one must use the full generalized Hooke's law. The reciprocal of the bulk modulus at fixed temperature is called the isothermal compressibility.`, 52 | modulus_shear:`Shear modulus or modulus of rigidity, denoted by G, or sometimes S or μ, is a measure of the elastic shear stiffness of a material and is defined as the ratio of shear stress to the shear strain.`, 53 | modulus_young:`Young's modulus E, or the modulus of elasticity in tension or compression (i.e., negative tension), is a mechanical property that measures the tensile or compressive stiffness of a solid material when the force is applied lengthwise.`, 54 | molar_volume:`The molar volume, symbol Vm, of a substance is the volume occupied by one mole of it at a given temperature and pressure. It is equal to the molar mass (M) divided by the mass density (ρ).`, 55 | neel_point:`Materials are only antiferromagnetic below their corresponding Néel temperature or magnetic ordering temperature. This is similar to the Curie temperature as above the Néel Temperature the material undergoes a phase transition and becomes paramagnetic. That is, the thermal energy becomes large enough to destroy the microscopic magnetic ordering within the material`, 56 | neutron_cross_section:`The concept of a neutron cross section is used to express the likelihood of interaction between an incident neutron and a target nucleus. The neutron cross section σ can be defined as the area in cm2 for which the number of neutron-nuclei reactions taking place is equal to the product of the number of incident neutrons that would pass through the area and the number of target nuclei.[page needed] In conjunction with the neutron flux, it enables the calculation of the reaction rate, for example to derive the thermal power of a nuclear power plant. The standard unit for measuring the cross section is the barn, which is equal to 10^−28 m2 or 10^−24 cm2. The larger the neutron cross section, the more likely a neutron will react with the nucleus.`, 57 | neutron_mass_absorption:`Neutron capture is a nuclear reaction in which an atomic nucleus and one or more neutrons collide and merge to form a heavier nucleus. Since neutrons have no electric charge, they can enter a nucleus more easily than positively charged protons, which are repelled electrostatically. Neutron capture plays a significant role in the cosmic nucleosynthesis of heavy elements. In stars it can proceed in two ways: as a rapid process (r-process) or a slow process (s-process). Nuclei of masses greater than 56 cannot be formed by thermonuclear reactions (i.e., by nuclear fusion) but can be formed by neutron capture.`, 58 | oxidation_states:`The oxidation state, or oxidation number, is the hypothetical charge of an atom if all of its bonds to different atoms were fully ionic. It describes the degree of oxidation (loss of electrons) of an atom in a chemical compound. Conceptually, the oxidation state may be positive, negative or zero. While fully ionic bonds are not found in nature, many bonds exhibit strong ionicity, making oxidation state a useful predictor of charge.`, 59 | period:`A period in the periodic table is a row of chemical elements. All elements in a row have the same number of electron shells. Each next element in a period has one more proton and is less metallic than its predecessor. Arranged this way, elements in the same group (column) have similar chemical and physical properties, reflecting the periodic law. For example, the halogens lie in the second-to-last group (group 17) and share similar properties, such as high reactivity and the tendency to gain one electron to arrive at a noble-gas electronic configuration.`, 60 | phase:`A state of matter is one of the distinct forms in which matter can exist. Four states of matter are observable in everyday life: solid, liquid, gas, and plasma. Many intermediate states are known to exist, such as liquid crystal, and some states only exist under extreme conditions, such as Bose-Einstein condensates, neutron-degenerate matter, and quark-gluon plasma, which only occur, respectively, in situations of extreme cold, extreme density, and extremely high energy.`, 61 | poisson_ratio:`Poisson's ratio (nu) is a measure of the Poisson effect, the deformation (expansion or contraction) of a material in directions perpendicular to the specific direction of loading. The value of Poisson's ratio is the negative of the ratio of transverse strain to axial strain. For small values of these changes, nu is the amount of transversal elongation divided by the amount of axial compression. Most materials have Poisson's ratio values ranging between 0.0 and 0.5. For soft materials, such as rubber, where the bulk modulus is much higher than the shear modulus, Poisson's ratio is near 0.5. For open-cell polymer foams, Poisson's ratio is near zero, since the cells tend to collapse in compression. Many typical solids have Poisson's ratios in the range of 0.2-0.3. The ratio is named after the French mathematician and physicist Siméon Poisson.`, 62 | quantum_numbers:`The Bohr model was a one-dimensional model that used one quantum number to describe the distribution of electrons in the atom. The only information that was important was the size of the orbit, which was described by the n quantum number. Schrodinger's model allowed the electron to occupy three-dimensional space. It therefore required three coordinates, or three quantum numbers, to describe the orbitals in which electrons can be found. The three coordinates that come from Schrodinger's wave equations are the principal (n), angular (l), and magnetic (m) quantum numbers. These quantum numbers describe the size, shape, and orientation in space of the orbitals on an atom.`, 63 | radius_calculated:`The atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding shells of electrons. Since the boundary is not a well-defined physical entity, there are various non-equivalent definitions of atomic radius. Four widely used definitions of atomic radius are: Van der Waals radius, ionic radius, metallic radius and covalent radius. Typically, because of the difficulty to isolate atoms in order to measure their radii separately, atomic radius is measured in a chemically bonded state; however theoretical calculations are simpler when considering atoms in isolation. The dependencies on environment, probe, and state lead to a multiplicity of definitions.`, 64 | radius_covalent:`The covalent radius is a measure of the size of an atom that forms part of one covalent bond. It is usually measured either in picometres (pm) or angstroms (Å), with 1 Å = 100 pm.`, 65 | radius_empirical:`The chart shows empirically measured covalent radii for the elements in picometers (pm or 1×10^−12 m), with an accuracy of about 5 pm.`, 66 | radius_vanderwaals:`The Van der Waals radius of an atom is the radius of an imaginary hard sphere representing the distance of closest approach for another atom. It is named after Johannes Diderik van der Waals, winner of the 1910 Nobel Prize in Physics, as he was the first to recognise that atoms were not simply points and to demonstrate the physical consequences of their size through the Van der Waals equation of state.`, 67 | refractive_index:`The refractive index (also known as refraction index or index of refraction) of a material is a dimensionless number that describes how fast light travels through the material. It is defined as n = c / v, where c is the speed of light in vacuum and v is the phase velocity of light in the medium. For example, the refractive index of water is 1.333, meaning that light travels 1.333 times slower in water than in a vacuum. Increasing the refractive index corresponds to decreasing the speed of light in the material.`, 68 | resistivity:`Electrical resistivity (also called specific electrical resistance or volume resistivity) is a fundamental property of a material that measures how strongly it resists electric current. A low resistivity indicates a material that readily allows electric current. Resistivity is commonly represented by the Greek letter ρ (rho). The SI unit of electrical resistivity is the ohm-meter (Ω⋅m). For example, if a 1 m3 solid cube of material has sheet contacts on two opposite faces, and the resistance between these contacts is 1 Ω, then the resistivity of the material is 1 Ω⋅m.`, 69 | series:`Many terms have been used in the literature to describe sets of elements that behave similarly. The group names alkali metal, alkaline earth metal, pnictogen, chalcogen, halogen, and noble gas are acknowledged by IUPAC; the other groups can be referred to by their number, or by their first element (e.g., group 6 is the chromium group). Some divide the p-block elements from groups 13 to 16 by metallicity, although there is neither a IUPAC definition nor a precise consensus on exactly which elements should be considered metals, nonmetals, or semi-metals (sometimes called metalloids).`, 70 | space_group_name:`A space group is the symmetry group of an object in space, usually in three dimensions. The elements of a space group (its symmetry operations) are the rigid transformations of an object that leave it unchanged. In three dimensions, space groups are classified into 219 distinct types, or 230 types if chiral copies are considered distinct. Space groups are discrete cocompact groups of isometries of an oriented Euclidean space in any number of dimensions. In dimensions other than 3, they are sometimes called Bieberbach groups.`, 71 | space_group_number:`There are 230 possible arrangements of symmetry elements in the solid state. They are called space groups. Any crystal must belong to one (and only one) space group. The space groups are numbered from 1 to 230 and each is represented by a space group symbol, e.g. space group number 19 has the symbol P212121.`, 72 | speed_of_sound:`The speed of sound is the distance travelled per unit of time by a sound wave as it propagates through an elastic medium. The speed of sound in any chemical element in the fluid phase has one temperature-dependent value. In the solid phase, different types of sound wave may be propagated, each with its own speed: among these types of wave are longitudinal (as in fluids), transversal, and (along a surface or plate) extensional. The speed of sound in an ideal gas depends only on its temperature and composition. The speed has a weak dependence on frequency and pressure in ordinary air, deviating slightly from ideal behavior.`, 73 | superconducting_point:`The critical temperature for superconductors is the temperature in kelvins (K) under which the electrical resistivity of a metal drops to zero.`, 74 | thermal_expansion:`Thermal expansion is the tendency of matter to change its shape, area, volume, and density in response to a change in temperature, usually not including phase transitions.`, 75 | valence_electrons:`A valence electron is an electron in the outer shell associated with an atom, and that can participate in the formation of a chemical bond if the outer shell is not closed; in a single covalent bond, both atoms in the bond contribute one valence electron in order to form a shared pair. The presence of valence electrons can determine the element's chemical properties, such as its valence — whether it may bond with other elements and, if so, how readily and with how many.` 76 | }) 77 | 78 | export { pTableProperties } --------------------------------------------------------------------------------