AbstractA semiorganic nonlinear optical (NLO) single crystal of bis(thiourea) manganese chloride (BTMC) is grown successfully by slow cooling technique using water as solvent at temperature 45 °C. The optically good quality crystal of BTMC was grown with dimension up to 8 × 8 × 2 mm3in a period of 2–3 weeks. The grown crystal crystallizes in orthorhombic crystal system which was confirmed by single crystal X-ray diffraction analysis. The various functional groups of BTMC were identified through FT-IR spectroscopic analysis. The lower cut-off wavelength of 280 nm was revealed from optical transmittance spectrum of UV. The mechanical behavior of BTMC crystal was analyzed by Vicker’s microhardness study and also the various mechanical parameters were determined. Vickers micro hardness test revealed, the titular crystal belongs to harder material category. The SHG efficiency is estimated from Kurtz-Perry powder method and it found to be 0.33 times than the reference material. The dielectric behavior, photo conducting nature and surface properties have been analyzed for grown BTMC crystal. The presence of synthesized elements was confirmed by EDAX study. The third order nonlinear optical susceptibility$$\chi^{\left(3 \right)}$$χ3of the material is measured using Z-scan technique and it is found to be 5.1202 × 10−14esu.