Inorganic crystal structure database (ICSD) and standardized data and crystal chemical characterization of inorganic structure types (TYPIX) - Two tools for inorganic chemists

Release 2002/2 of the Inorganic Crystal Structure Database (FIZ Karlsruhe, Germany, and Institute Laue–Langevin, Grenoble, France) contains 62 entries in space group P31 and ten entries in space group P32 for 49 different materials including eight families with two or more isostructural members. The structural criteria for ferroelectricity are satisfied for 16 new structure types at a confidence level that depends on the reliability of each determination. LaBGeO5, a mineral with stillwellite structure, was previously reported as ferroelectric and forms an additional family with seven other members or related structures that satisfy the criteria. Ten structures reported in space group P31 or P32 are dubious or incorrect, with atomic coordinates that satisfy supergroup symmetry. One material is probably pyroelectric but is unlikely to become ferroelectric, and three others are either incompletely solved or incompletely refined. Among the predicted new ferroelectrics are Cu2BaGeS4, Fe3(Fe,Si)O4(OH)5, Se4S5, K2HCr2AsO10, IV-RbNO3, Rb2Sc(NO3)5, Na3ReO5, Nd14(GeO4)2(BO3)6O8, CsHgCl3, Ba2Cu2AlF11, KYF4, SrS2O6·4H2O, Cu3PbTeO6(OH)2, ReH(CO)4, Ni2(NH3)9Mo(CN)8·2H2O and the 6T polytype of Ca1.89Ta1.80Sm0.16Ti0.10O7, in addition to β-LaBSiO5, PbBAsO5 and BaBAsO5 in the stillwellite family.

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Bond analyses of borates from the Inorganic Crystal Structure Database

Acta Crystallographica Section B Structural Science ◽

10.1107/s0108768106018520 ◽

2006 ◽

Vol 62 (5) ◽

pp. 702-709 ◽

Cited By ~ 37

Author(s):

Daqiu Yu ◽

Dongfeng Xue

Keyword(s):

Crystal Structure ◽

Building Blocks ◽

Low Complexity ◽

Bond Valence ◽

Inorganic Crystal Structure Database ◽

Bonding Structure ◽

Structural Evaluation ◽

Structure Database ◽

Inorganic Crystal ◽

Crystal Structure Database

Various fundamental building blocks (FBBs) are observed in the crystallographic structures of oxoborates available in the Inorganic Crystal Structure Database, Version 1.3.3 (2004); the occurrence of borate groups with low complexity is dominant. Bond-valence parameters d 0 of B—O bonds in 758 oxoborates with various FBBs have been calculated using the bond-valence sum model. Some discrepancies in the d 0 values obviously occur if the detailed configurations of FBBs in borate crystals are considered; d 0 is sensitive to the chemical bonding structure of B atoms in the crystallographic framework. Moreover, d 0 values are affected by the existence of interstitial atoms and the substitution of other anionic groups. In addition, the d 0 parameters for B—N, B—S, B—P and B—F bonds are also calculated statistically. Some suitable d 0 data for various borate FBBs are recommended according to their particular configurations, especially for those with low complexity. On the basis of the proposed linear relationship between calculated nonlinear optical (NLO) coefficients of borates and the current d 0 values for various FBBs, it is found that the d 0 values may be regarded as a useful parameter for pre-investigating the NLO properties of borates, leading to an efficient structural evaluation and design of novel borates.

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Recent developments in the Inorganic Crystal Structure Database: theoretical crystal structure data and related features

Journal of Applied Crystallography ◽

10.1107/s160057671900997x ◽

2019 ◽

Vol 52 (5) ◽

pp. 918-925 ◽

Cited By ~ 25

Author(s):

D. Zagorac ◽

H. Müller ◽

S. Ruehl ◽

J. Zagorac ◽

S. Rehme

Keyword(s):

Crystal Structure ◽

Structure Data ◽

Crystal Structure Data ◽

Theoretical Data ◽

Inorganic Crystal Structure Database ◽

Structure Database ◽

Inorganic Crystal ◽

Recent Developments ◽

New Compounds ◽

Crystal Structure Database

The Inorganic Crystal Structure Database (ICSD) is the world's largest database of fully evaluated and published crystal structure data, mostly obtained from experimental results. However, the purely experimental approach is no longer the only route to discover new compounds and structures. In the past few decades, numerous computational methods for simulating and predicting structures of inorganic solids have emerged, creating large numbers of theoretical crystal data. In order to take account of these new developments the scope of the ICSD was extended in 2017 to include theoretical structures which are published in peer-reviewed journals. Each theoretical structure has been carefully evaluated, and the resulting CIF has been extended and standardized. Furthermore, a first classification of theoretical data in the ICSD is presented, including additional categories used for comparison of experimental and theoretical information.

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