Geometry of Molecules. Part 7. Interatomic Distances, Bond Angles and Strain Energies in some Rotenes and Related Spirocompounds by the IMO Method

The electronic and molecular structure of some three-, four- , five - and six-membered ring rotenes are studied by the iterative maximum overlap method. The shape and size of these unusual, highly strained, systems are considered and the strain destabilization energies are estimated. The local bond characteristics are discussed in terms of variable hybridisation indices. Studied properties include spin-spin coupling constants, C-H stretching frequencies, thermodynamic proton acidities, diamagnetic susceptibilities and the diamagnetic contribution to the nuclear magnetic shielding