FT-Raman, FT-IR spectroscopic and DFT studies of hexaphenoxycyclotriphosphazene

The FTIR and FT Raman measurements of zero G(c0)'-H and first G(c1)'-H generations of phosphorus dendrimer built from cyclotriphosphazene core with phenoxy and deuterophenoxy terminal groups have been performed. In order to evaluate how much the frequencies, shift when changing the electronics of the system the FTIR and FT Raman spectra of phosphorus-containing dendron with five terminal oxybenzaldehyde and one ester function G(ci)' have been also studied. Structural optimization and normal mode analysis were obtained for G(c0)'-H and G(c0)'-D by the density functional theory (DFT). It is discovered that dendrimer molecule exists in a stable conformation with six phenoxy terminal groups spaced above and below the flat cyclotriphosphazene core. Optimized geometric bond length and angles obtained by DFT show good agreement with a previously-published X-ray study. The phenoxy terminal groups are characterized by the well-defined line at 993 cm(-1) in the experimental Raman spectrum of G(c0)'-H and by line at 960 cm(-1) in the Raman spectrum of G(c0)'-D. Relying on DFT calculations a complete vibrational assignment is proposed for the studied dendrimers. The frequencies and relative intensity of the bands at 1589, 1487 cm(-1) in the IR spectra show marked difference in dependence of the substituents on the aromatic ring. (C) 2016 Elsevier B.V. All rights reserved.