Squares repulsion energy coefficients

Spot tests, 1, 552 Square antiprisms dodecahedra, cubes and, 1, 84 eight-coordinate compounds, 1,83 repulsion energy coefficients, 1, 33, 34 Square planar complexes, 1,191, 204 structure, 1, 37 Square pyramids five-coordinate compounds, 1,39 repulsion energy coefficients. 1,34 Squares... 

The two most stable structures, the square antiprism and the dodecahedron, are considered in more detail below. The square antiprism is observed to be much more common than the dodecahedron, in agreement with the above repulsion energy coefficients. 

Calculations, based on VSEPR theory so as to minimize repulsion between ligands in some of these afore-mentioned forms, have shown that repulsion energy coefficients for the square antiprism, dodecahedron, and cube are about the same but that the antiprism should be the most stable configuration for a MLg polyhedron (S). This principle has also been applied to K4[Mo(CN)g] 2H20, for which, in contrast... 

Beryllium, bis(t ifluo oacetylacetone)-gas chromatography, 560 Berzelius s conjugate theory, 4 Bicapped pentagonal prisms repulsion energy coefficients, 34 twelve-coordinate compounds, 100 Bicapped square antiprisms repulsion energy coefficients, 33,34 ten-eoordinate compounds, 98 1, r-Binaphthyl, 2,2 -bis(diphenylphosphino)-complexes... 

Table 5 A comparison between quantum-mechanical and force-field treatment of dispersion and repulsive contributions to the free energy of solvation. The force field is given under method, and for each solvent the first line gives the root mean square deviation (rmsd, in kcal/ mol) and the second line gives the coefficient c that gives the best fit of y = cx with y being the force-field results and x being the quantum-mechanical results. All results are from ref 30...

This parameter is actually the second virial coefficient for the monomers in the solvent medium. Clearly, v is temperature-dependent. At higher temperatures, as the monomers collide against each other, the interaction energy is repulsive (positive) so that the first term inside the square bracket of the above equation dominates over the second term. Therefore, v is positive at higher temperatures. At lower temperatures, the monomers tend to attract (m is negative), and now the second term dominates over the first term so that v is negative. The temperature dependence of v is sketched in Figine 2.8c. 

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