Berry pseudorotation coordinate

CH3CN, 33-11, 33 H20, 34, 35-jCH3CN, and 37jCH3CN represent nearly ideal or (more or less) distorted square pyramids, with the carbon atom Cl in the apical position. In most cases, the geometries of the Si-coordination polyhedra in the crystal are located on the Berry-pseudorotation coordinate (pivot atom Cl). 

Percentage displacement along the Berry pseudorotation coordinate. 

Fig. 55. Schematic progress along a Berry pseudorotation coordinate, with corresponding molecular structures and N-Si-N and O-Si-O angles (degrees).83 Reproduced with permission...

Fig. 19. Structures of nickel complexes lying away from the Berry pseudorotation coordinate...

Fig. 12.8 Wave function and energy changes along a Berry pseudorotation coordinate. Note relative energies of the e ( >w) and a, and e (C .) levels. (From Rossi, A. R. Hoffmann, R. Inorg. Chem. 1975, 14, 365-374. Reproduced with permission.)...

Correlation diagram along the Berry pseudorotation coordinate as one progresses from a trigonal bipyramidal to a square pyramidal electron configuration. [After Rossi, A. 

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