Structure data, crystal

ICSD FIZ Karlsruhe. Germany NIST, USA crystal structure data of inorganic compounds nu- meric. factual 65 000 journals STN online, CD-ROM biannu- ally wuTw.fiz-infoT- mationsdien- ste.de... 

Table 8. Properties and Crystal Structure Data for Important Actinide Binary Compounds...

The pyrimidine ring is virtually flat. Its corrected bond lengths, as determined by a least-squares analysis of the crystal structure data for a unit cell of four molecules, are shown in formula (2) (60AX80), and the bond angles derived from these data show good agreement with those (3) derived by other means (63JCS5893) for comparison, each bond... 

Reaction center hydropathy plots agree with crystal structural data... 

Table 3. Crystal structure data for some carbyncs...

Angles between Bonds, from Crystal Structure Data ... 

This by no means exhaustive discussion may serve to indicate the value of the information provided by magnetic data relative to the nature of the chemical bond. The quantum-mechanical rules for electron-pair bonds are essential to the treatment. Much further information is provided when these methods of attack are combined with crystal structure data, a topic which has been almost completely neglected in this paper. It has been found that the rules for electron-pair bonds permit the formulation of a set of structural principles for non-ionic inorganic crystals similar to that for complex ionic crystals the statement of these principles and applications illustrating their use will be the subject of an article to be published in the Zeitschrift fur Kristallographie. 

The crystal structure data are taken from Wyckoff, "International Critical Tables, except where otherwise noted. Inter-atomic distances referred to Goldschmidt are from Goldschmidt, Skrifter Det. Norske Videnskaps-Akad. Oslo I. Maiem.-Naturvid. Klasse, 1926, No. 2. 

This theoretical result is completely substantiated by experiment. Goldschmidt,31 from a study of crystal structure data, observed that the radius ratio is large for fluorite type crystals, and small for those of the rutile type, and concluded as an empirical rule that this ratio is the determining factor in the choice between these structures. Using Wasastjerna s radii he decided on 0.67 as the transition ratio. He also stated that this can be explained as due to anion contact for a radius ratio smaller than about 0.74. With our radii we are able to show an even more satisfactory verification of the theoretical limit. In Table XVII are given values of the radius ratio for a large number of compounds. It is seen that the max-... 

Tab. 3.1 DNA-binding proteins that have been inhibited by polyamides. The known DNA binding motifs from NMR or crystal structure data are shown. Significant groove contacts and proposed mechanism of polyamide inhibition are also shown for each protein...

Table II. Crystal Structure Data for PbTX-1 Dimethyl Acetal...

Table III. Crystal Structure Data for Dihydro PbTX-1...

Identification of proteins that bind to Z-DNA added one further step to the establishment of the presence of Z-DNA in vivo and its possible biological role. Herbert and Rich [22] demonstrated an in vitro assay system where one type of double-stranded RNA adenosine deaminase, called DRAD-binding Z-DNA. There are evidences that topoisomerase II from Drosophila, hiunan and calf thymus recognizes a number of DNA shapes, including Z-DNA [34,35]. Bloomfield and coworkers [36] have found that the condensation of plasmids is enhanced by Z-DNA conformation in d(CG)n repeats. The information related to B-Z transition [31], the effect of ligands on it [28,29] and X-ray crystal structure data [37,38] appear to suggest that the possible biological role of this polymorphic form of DNA will be soon established. 

Refluxing [C x i2 tc)] in CHCI3 yields a compound which analyses as Cu3(Et2C tc)2Cl 124). The analogous butyl compounds could be prepared by the reaction of 1 mole [Cu(Bu2C tc)]4, 2 moles Cu and 1 mole X2 (X = C1, Br) in CS2. Molecular weight determinations in benzene show an association factor 3 and infrared data point to terminal halogen atoms 99). No crystal structure data of these compounds are available. 

The similarity of the structures of rutile, CaCl2 and marcasite also comes to light by comparison of their crystal structure data (Table 17.2). The space groups of CaCl2 and marcasite (both Pnnm) are subgroups of the space group of rutile. The tetragonal sym-... 

Strukturbericht 1-7. Akademische Verlagsgesellschaft, 1931-1943. Structure Reports 8-58. Kluwer, 1956-1990. Collection of crystal structure data of one year, published annually. 

E. Parthe, L. M. Gelato, The standardization of inorganic crystal-structure data. Acta Crystallogr. A40 (1984) 169. 

The crystal structure data suggest some sp2 character for the silicon and carbon atoms of the double bond, but there is a high degree of ir-... 

Perhaps the most simple crystals in this class are the alkaline earth oxides. They are II-VI compounds and have rocksalt crystal structures. Data for their hardnesses versus their bond moduli (optical band gaps per molecular volumes) are displayed in Figure 11.4. 

Crystal structure data are indispensable for the discussion of the conduction mechanism in the cation radical salts based on the unsymmetrical complexes. In 2002,... 

However, its was found possible to infer all four microscopic tensor coefficients from macroscopic crystalline values and this impossibility could be related to the molecular unit anisotropy. It can be shown that the molecular unit anisotropy imposes structural relations between coefficients of macroscopic nonlinearities, in addition to the usual relations resulting from crystal symmetry. Such additional relations appear for crystal point group 2,ra and 3. For the monoclinic point group 2, this relation has been tested in the case of MAP crystals, and excellent agreement has been found, triten taking into account crystal structure data (24), and nonlinear optical measurements on single crystal (19). This approach has been extended to the electrooptic tensor (4) and should lead to similar relations, trtten the electrooptic effect is primarily of electronic origin. 

Mechanisms involving axial coordination of the optically active amine have also been invoked, and crystal structure data on RCo(DMG)2B complexes, where R is alkyl or (R)-l-(methoxycarbonyl)ethyl, and B is (R )-a-methylbenzylamine, were obtained (316, 317). Because deuteration of the (R)-methoxycarbonyl complex gave (5)-methylpropionate-2-d, it was concluded that Co—C bond cleavage occurred with inversion of configuration at the carbon (317). It would be useful to know the mechanistic details of this step, which could involve attack by D+, DCo(III), or coordinated D, as well as D2, for it is an unusual, if not unique, observation [contrast with the usual retention mechanism outlined in Eq. (39)]. 

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