PHYSICS · Multi-part · Fermi University Physics · Mathematical Methods for Physics · Atomic, Molecular & Optical Physics · Molecular structure and spectra
Invariance, Ch Character tables at work: vibrations, selection rules and splitting
Problem
Phosphorus trichloride, PCl3, is pyramidal with point group C3v, P on the C3 axis and the three Cl atoms forming the base. Use the C3v character table (classes E, 2C3, 3σv; basis functions z→A1, (x,y)→E, Rz→A2, (Rx,Ry)→E).
((a)) Find χ3N and decompose it.
((b)) Find Γvib and the number of distinct vibrational frequencies.
((c)) Decompose the direct product A2⊗E.
((d)) Using the vanishing integral theorem, decide whether a transition from the totally symmetric ground state (A1) to an excited state of species A2 is allowed by electric-dipole absorption.