A complete normal coordinate analysis was performed for five-coordinate non-rigid triarylantimony diester SbPh₃(O₂CR₂), known to be a bioactive molecule, using Wilson G-D matrix method and Urey Bradley force field. The study of vibrational dynamics was performed using the concept of group frequencies and band intensities.

A complete normal coordinate analysis was performed by two different methods: a classical Wilson's G-F matrix method and the semi-empirical molecular orbital PM3 method, for a five coordinate tris(𝑝-fluorophenyl)antimony di(𝑁 -phenylglycinate) [(𝑝-FC₆H₄)₃Sb(O₂CCH₂NHC₆H₅)₂], known to be an in vitro antitumour molecule.