Raman scattering of complex sodium aluminum hydride for hydrogen storage

Complex hydride materials are currently under investigation for potential use in hydrogen storage applications. In this report, the Raman spectra of sodium aluminum hydride (NaAlH4) were collected using an excitation laser line at 633 nm. The interpretation and assignment of the observed spectrum of NaAlH4 was aided by cluster-based density functional calculations, using hybrid density functional theory [B3LYP/6-31+G(d,p)], enabling the reliable interpretation of characteristic Raman bands. The assignment and identification of internal vibrational, torsional, and lattice vibrational modes are discussed, providing spectroscopic probes for future physicochemical studies following structural and systemic evolution during the hydriding/dehydriding processes of NaAlH4.