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Coordination Polyhedra LaOn in Crystal Structures

“…The lanthanum C.N.s were found to vary from 4 to 12, the most frequently encountered values being 8 and 9, which is consistent with the published data [10]. Using the TOPOS software [8], characteristics of the lanthanum VDP were calculated for all 553 compounds (Table 1) and statistical analysis of the results was carried out.…”

“…In databases [5,6], these conditions are met for 553 compounds containing 762 crystallographically nonequivalent sorts of La(III) atoms. The full list of compounds is available from the authors: vologzhanina@fromru.com.Since in 96 compounds, all or some of the hydrogen atoms have not been located during the structure determination, the coordinates of the missing atoms were calculated at the first investigation stage using the HSite program [7] included in the structure-topological TOPOS package [8]. Using the method of intersecting spheres [9], according to which any two atoms are considered to be chemically bonded if the common face of their Voronoi-Dirichlet polyhedra (VDP) is described by the I 4 , I 3 , or I 2 intersection, the coordination numbers (C.N.s) of all atoms were determined.…”

Manganese Stereochemistry in the Structures of Oxygen-Containing Compounds

“…The primary crystal chemical information was selected from databases of inorganic [3] and coordination [4] compounds using the TOPOS program package [5]. The data on the compound structures were taken into account only when the following conditions were fulfilled simultaneously: (1) the crystal structure was determined with an R -factor of ≤ 0.1; (2) coordinates of all atoms present in the compound including hydrogen were known; (3) no random distribution of manganese or oxygen atoms was found in the structure, and (4) manganese atoms had integer oxidation numbers.…”

The coordination polyhedra PrOn in the crystal structure

“…The above conditions were satisfied by structural data for 235 complexes containing 331 crystallographically nonequivalent sorts of Pr atoms, including 302 for Pr III and 29 for Pr IV . For 75 complexes, the coordinates of all or part of the H atoms were not reported; for this reason, we located the missing H atoms with the HSite program [7] of the TOPOS structural-topological program package [8] and their coordinates were included in all subsequent computations.…”

“…The parameters of the VD polyhedra of Pr atoms were calculated for all 235 complexes with the TOPOS program package [8] and the results obtained were statistically analyzed. The C.Ns.…”