●●● physical properties in the PAULING FILE

●● features

The Physical Properties section of the PAULING FILE collects experimental and calculated data for a broad range of intrinsic physical properties (see below) of inorganic compounds in the solid (crystalline) state. When relevant, the entries also contain information about synthesis and sample preparation, as well as information that helps to establish the links to Phase Diagram and Crystal Structure entries, such as colloquial names, crystallographic data, limits of stability with respect to temperature, pressure or composition. Processing is literature-oriented and each database entry groups selected data extracted for a particular phase in a particular publication. Focus is on the characterization of inorganic substances (single-phase samples), rather than on the optimization of materials.

The properties are stored in four different ways:
● numerical data and experimental details defining their determination
● description of figures (Y vs. X)
● property classes such as superconductor, ferroelectric, etc.
● keywords indicating the existence of particular data, e.g. spectra
Symbols recommended by the Handbook of Chemistry and Physics [1] are used throughout the database; numerical values are given in as-published units and SI units.

● concept
Storage of properties and conditions for their determination. Green fields belong to reference tables, thanks to which symbols, units, unit conversion, and ranges of magnitude can be controlled.

●● data selection

Data are taken from primary literature. Each database entry corresponds to one combination inorganic phase - publication, but can contain several numerical values, figure descriptions, and references to additional data. For an investigation of a compound through a temperature- or pressure-induced structural phase transition there will be two database entries, e.g. one for the rt modification and one for the lt modification. When no information is provided in the paper, ferroelectric transitions are by default considered to be accompanied by structural changes, magnetic, electric or superconducting transitions not. For a complete solid solution between two binary compounds, three database entries will be created: one for each binary border compound and one for the ternary system.

An indicative list of properties selected for the PAULING FILE is given below.

●●● statistics

●● distribution according to journal

●● distribution according to publication year

202'431 database entries processed 03.2024

●● distribution according to chemical class

● 1 or 2 elements	● 3 elements	● 4 or more elements
58'162	67'713	76'556

●● distribution according to property class

● property class 1 electronic and electrical properties 2 magnetic properties 3 mechanical properties 4 optical properties 5 phase transitions 6 superconductor properties 7 thermal and thermodynamic properties ● data category from bottom to top: - numerical values - figure descriptions - additional data

●●● list of properties

Below are listed the main properties considered in the PAULING FILE, grouped into categories. Items in square brackets are keywords, for which numerical values are in principle not extracted. Primary properties, to which particular importance is paid for the storage of numerical values, are emphasized with bold characters.

+ electronic and electrical properties
+ ferroelectricity
+ magnetic properties
+ mechanical properties
+ optical properties
+ phase transitions
+ superconductivity
+ thermal and thermodynamic properties


references

[1] Handbook of Chemistry and Physics, 78th edition, Eds. D.R. Lide, H.P.R. Frederikse, Boca Raton: CRC Press, 1997 and more recent editions.