Site position multiplicity

For a definition of space group spectra see Section 10.5. Spectra for all space groups are arranged below (Tables A2.1-A2.10) in order of decreasing symmetry. The multiplicities of the Wyckoff positions, m, are given across the top of each table. The symmetries of sites with multiplicity 1 are given at the end of each line followed by structure types that crystallize in that space group (site symmetries in parentheses refer to positions of multiplicity 2). 

Bazykin GA, Kondrashov FA, Ogurtsov AY, Sunyaev S, Kondrashov AS. Positive selection at sites of multiple amino acid replacements since rat-mouse divergence. Nature 2004 429 558-562. 

Positions. This field contains standardized information about possible locations (or sites) that can accommodate points (or atoms) in the unit cell and corresponding reflection conditions. Reflection conditions show the limitations on the possible combinations of Miller indices that are imposed by the symmetry of the space group and these will be discussed in Chapter 2, sections 2.12.3 and 2.12.4. Each record in this field corresponds to one site and each site is listed starting with the multiplicity of the site position (integer numbers, 8,4,4,..., 2) followed... 

Using the International Tables for Crystallography describe every atom in terms of the multiplicities and Wyckoff letters of their site positions and establish the content of the unit cell, the simplest chemical formula and the number of formula units (Z) per unit cell. 

The last column in Table 7.2 contains site occupancies by all atoms in the format required by LHPM-Rietica. The occupancy of each site ( ) is given as a product of the population parameter (g) and site multiplicity (m) divided by the multiplicity of the general site position (A ) ... 

Some software products, e.g. GSAS, require specification of the population parameters as g, while the multiplicities of site positions are automatically included by the program. 

Aromatic, dye and other chromophore-containing molecules have a variety of special physical properties. CDs modified by these groups exhibit many new properties. Since the chromophore can be used as a spectral probe, this makes it possible to apply UV, fluorescence, circular dichroism spectroscopy and other means in the molecular recognition field. For example, CD phosphate has a positive electron deficient center, which is a new recognition site for multiple identification of amino acids. 

Vinyl monomers fi om carbohydrates have been prepared by selective enzyme-catalyzed transformations. Motivations for such work have been to i) selectivity place vinyl functional groups at one site of multiple possible positions... 

The interest in different ligand combinations on a metal center is due to the multiple reactive coordination sites offering multiple reactive positions at the neutral electrophilic metal center on a pseudo bent metallocene coordination sphere. The structure of the borohydride complex (COT)U(BH4)2(OPPh3) (Baudry et al. 1990a) consists of discrete molecules with a piano stool configuration, it is the first to be determined for a mono-COT U derivative. Mixed ligand Th derivatives can be obtained by the reaction... 

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