Experimental and theoretical Raman analysis of functionalized diamantane

Abstract

Diamantane functionalized with amino, hydroxyl and thiol groups has been analyzed by Raman spectroscopy. The peaks in the spectra were assigned by supporting density functional theory computations. Two fingerprint regions for a fast determination of functionalization type and site were identified. With their help we can distinguish two different sites of the functional group. Functionalization in the 1-position leads to Raman activation and splitting of degenerate vibrational modes and hence to a more complex Raman spectrum and strong shifts of several modes. Small shifts of the same modes, on the other hand, indicate functionalization in the 4-position. We observe an anomaly in the mass dependence of the functional group, which we assign to the influence of the electronegativity on the vibrational frequency. Additionally, we can distinguish between the functional groups by the characteristic bands of the stretch vibration.