Third, Fourth and Fifth Order Vibrational Problems by the Method of Isotani

Abstract

A new technique has been adopted in this paper in solving the secular equation |H - ΔE|= 0 where H = GF, so as to get the force constants for a series of molecules of the type XY₃Z, XY₃ZW and XY₃ZVW belonging to the point group C_3V involving third, fourth and fifth order vibrational problems respectively.