A model for stretch-bend interactions in molecular force fields

Mills, I. (1963) A model for stretch-bend interactions in molecular force fields. Spectrochimica Acta, 19 (9). pp. 1585-1594. ISSN 0371-1951 doi: 10.1016/0371-1951(63)80017-X

Abstract/Summary

Interaction force constants between bond-stretching and angle-bending co-ordinates in polyatomic molecules have been attributed, by some authors, to changes of hybridization due to orbital-following of the bending co-ordinate, and consequent changes of bond length due to the change of hybridization. A method is described for using this model quantitatively to reduce the number of independent force constants in the potential function of a polyatomic molecule, by relating stretch-bend interaction constants to the corresponding diagonal stretching constants. It is proposed to call this model the Hybrid Orbital Force Field. The model is applied to the tetrahedral four co-ordinated carbon atom (as in methane) and to the trigonal planar three coordinated carbon atom (as in formaldehyde).