Theoretical study of “sandwich” clusters of fused magnesium porphyrin oligomers with alkali metal atoms

Abstract

The structural characteristics, energies, and spectroscopic properties of two-layer and multilayer “sandwich” clusters in which rings (layers) of fused porphyrin oligomers Mg2P2 and Mg4P4 (P = C20H12N4) are separated by (Li) n metal interlayers containing from 8 to 32 lithium atoms have been calculated by the density functional theory B3LYP method. The trends in the changes in these characteristics have been scrutinized as a function of the number of introduced Li atoms and the size and number of porphyrin layers. Calculations predict the high energetic stability and possibility of the existence of these sandwiches as paramagnetic clusters with mobile intercalated lithium ions. The latter, like intercalated graphite clusters, are expected to exhibit high electronic and ionic conductivity. The most favorable (with low or zero barriers) channels of migration of metal ions between the porphyrin layers are discussed.