Structures and nonlinear optical properties of molecular crystals DMCC and DBCC

Abstract: Structures and nonlinear optical properties of dimethylcroconate (DMCC) and dibenzoylcroconate (DBCC) are reported. The SHG active DMCC crystal packed in non-centrosymmetric P212121 space group. The DBCC crystal has a host–guest structure and crystallized in centrosymmetric P21/n space group. In DBCC crystal, the host DBCC molecules build channels along the b direction with the guest benzene molecules trapped in the channels. DSC, XRD, SHG and structural studies reveal that these benzene molecules can be removed at 90°C, accompanying the loss of the centro-symmetry and resulting in the SHG active new crystalline phase. [Copyright &y& Elsevier]