Synthesis\nand Large Crystal Growth of a Noncentrosymmetric\nSodium Methylsulfanetriol Borate Lewis-Adduct: Na(S(OH)<sub>3</sub>CH<sub>3</sub>)(BO<sub>3</sub>)

A new metal methanesulfonate-derived borate compound,\nNa(S(OH)<sub>3</sub>CH<sub>3</sub>)(BO<sub>3</sub>) (NMSB), was successfully\nsynthesized.\nNMSB crystallizes in the cubic and acentric space group <i>P</i>2<sub>1</sub>3 (no. 198) and may be grown as large, high-quality\nmillimeter to centimeter-sized crystals through spontaneous crystallization\nunder ambient conditions [<i>a</i> = 8.7714(2) Å, <i>Z</i> = 4]. NMSB exhibits a three-dimensional structure composed\nof a new methylsulfanetriol functional group, [S(OH)<sub>3</sub>CH<sub>3</sub>]<sup>2+</sup>, and extended H-bonding with planar [BO<sub>3</sub>]<sup>3–</sup> groups. The framework is formed by the\nLewis acid–base reaction of SO: → HOB, structurally\nand charge-balanced by distorted NaO<sub>6</sub> octahedra. The composition,\nstructure, and facet-indices are confirmed by SC-XRD, PXRD, EDS, and\nFT-IR spectroscopy. UV–vis diffuse reflectance spectroscopy\nshows that NMSB is transparent in the UV–vis region with an\noptical absorption edge in the deep-UV region, λ<sub>abs</sub> < 200 nm. NMSB is thermally stable up to 200 °C and is highly\nsoluble in water. This new compound exhibits unique borate chemistry\nas well as insights into underexplored methanesulfonate-derived salts\nas optical materials.