Structural and electronic properties of the metal cluster‐based compounds including high concentration of solvent molecules

Recrystallization of Cs-2[Mo6X14] (X=Cl, Br) was examined using typical organic solvents, i. e., methanol (CH3OH), acetone (CH3COCH3) and dichloromethane (CH2Cl2) in order to modify crystal structures and optoelectronic properties by promoting purity or inducing insertion of guest molecules. To this context, we performed recrystallization in solvent liquid and exposure of Cs-2[Mo6X14] to vapor of those solvents. Subsequent single crystal X-ray diffraction analyses revealed that three new types of compounds which contain high concentration of guest organic solvent molecules were obtained. Indeed, the newly found structures are Cs-2[Mo6Cl14] . 3CH(3)OH and Cs-2[Mo6X14] . 6CH(3)COCH(3) belonging to triclinic P1? space group, and Cs-2[Mo6X14] . 4CH(2)Cl(2) belonging to tetragonal P4/mnc space group. Although breaking of centrosymmetry by insertion of the guest molecule is interesting in terms of optoelectronic properties, all those new compounds belong to centrosymmetric space groups. As DFT calculations for those new compounds show that the guest molecules, such as CH3OH, do not affect the atomic arrangements and electronic features of the [Mo6X14](2-) cluster based unit, they incorporated with the lattice while keeping with the electrostatic interaction between the [Mo6X14](2-) and Cs+ ions regardless of the very high concentration of the guest solvent molecules.