Theoretical study of encapsulated alkali metal atoms in nanoporous channels of ITQ-4 zeolite: One-dimensional metals and inorganic electrides

The nature of the atomic geometry and electronic ground and excited states of a series of inorganic electrides, M-ITQ-4 (M=Na, K, Rb, Cs) were investigated. It was observed that the Na atoms formed a perfect one-dimensional (1D) metal undergoing Peierls distortion and con-comitant dimerization. A far infrared excitation peak in Na at∼0.35 eV that could be ascribed to the Peierls distortion was also discussed. It was found that the organic electrides had a higher thermal stability.