Crystal Structure and Theoretical Calculation of 1,4-Bis-(1-ferrocenesulfonyl-2-benzimidazolyl) Butane

A N,N′-bisferrocenesulfonyl bisbenzimidazole compound 1,4-bis(1-ferrocenesulfonyl-2-benzimidazolyl) butane was prepared. Its crystal structure was determined. The crystal belongs to triclinic with space group P-1 and a=0.87241(13) nm, b=0.97553(15) nm, c=1.4120(2) nm, and α=83.041(2) °, β=72.454(2)°, γ=69.732(2)°, the unit cell volume V=1.0746(3) nm3, the molecule number in one unit cell Z=1, the absorption coefficient μ=1.191 mm−1, the calculated density Dc=1.584 g/cm3. The theoretical investigation of the compound as a structure unit was fully optimized by B3LYP/6-31G method in Gaussian 03 package, and the most stable structure of the compound in theory was obtained. The two results were compared. The optimized structure was in accordance with the crystal structure in the main, suggesting that the molecular geometry optimization of the structures was reliable and the calculation method used was reliable. The distribution of atomic charges and the energy, and composition of frontier molecular orbits were analyzed. Thermal analysis indicated that it is stable before melting.