Single crystal growth, structural characterization, thermal and optical properties of a novel organometallic nonlinear optical crystal: MnHg(SCN)4(C2H5NO)2

A novel potentially useful organometallic nonlinear optical crystal, manganese mercury thiocyanate-bis(N-methylformamide), MnHg(SCN)4(C2H5NO)2 (MMTN) has been prepared, and large highly-optical quality single crystals with dimensions up to 29×28×14 mm3 have been grown. The structural characterization, thermal and optical properties of the grown crystals are investigated. The growth morphology was obtained by indexing the X-ray powder diffraction data and compared with that deducing from the single crystal structure data using the Bravais–Friedel–Donnay–Harker model. The thermal analysis reveals that MMTN crystal possesses good physicochemical stability. The specific heat of the crystal is 635.1 J mol−1 K−1 at 300 K. The thermal expansion coefficient along the a, b, and c axis is α1=6.18×10−5 K−1, α2=3.91×10−5 K−1 and α3=9.53×10−6 K−1, respectively. The laser damage threshold of MMTN crystal is about 225.7 MW/cm2 with pulse width of 18 ns at 1064 nm. The powder second harmonic efficiency of the crystal is about 1.1 pm/V and the UV transparency cutoff is 354 nm, which are interpreted on the basis of the crystal structure with the Molecular Orbital theory using a GAUSSIAN03 program.