Structural stability and electronic property of sandwich clusters (CmHm)Mn(CnHn) (m,n=5,6) following an 18-electron principle

The structural stability and electronic property of sandwich clusters (CmHm)Mn(CnHn) (m,n=5,6) have been studied by using the scalar relativistic all-electron density functional theory. It is found that the manganese sandwich complex (C5H5)Mn(C6H6) is a stable cluster with large binding energy and HOMO-LUMO gap, as well as Fe(C5H5)2 and Cr(C6H6)2, following the 18-electron principle. Moreover, the anionic cluster [Mn(C5H5)2]− with 18 valence electrons is found more stable than Mn(C5H5)2 in both high spin and low spin states with 17 valence electrons. The detailed frontier orbitals and harmonic vibrational spectra analysis are also given and discussed.