New noncentrosymmetric material--[N(CH3)4]ZnCl3: polar chains of aligned ZnCl4 tetrahedra.

ABSTRACT

A new organically templated noncentrosymmetric polar zinc chloride, [N(CH(3))(4)]ZnCl(3), has been synthesized hydrothermally, and the structure was determined by single crystal X-ray diffraction. The reported material exhibits a unidimensional crystal structure consisting of chains of anionic ZnCl(4) tetrahedra that are separated by [N(CH(3))(4)](+) cations. Second-harmonic generation (SHG) measurement on the noncentrosymmetric [N(CH(3))(4)]ZnCl(3), using 1064 nm radiation, indicate the material has a SHG efficiency of approximately 15 x alpha-SiO(2). Additional SHG measurements indicate the material is nonphase-matchable (type 1). In addition, converse piezoelectric measurements revealed d(33) values of 10 pm/V. Thermogravimetric analysis, UV-vis diffuse reflectance, and infrared spectroscopy were also performed, as were electronic structure calculations. Crystal data [N(CH(3))(4)]ZnCl(3), orthorhombic, space group Pmc2(1) (No. 26), with a = 7.2350(14) A, b = 8.8210(18) A, c = 15.303(3) A, V = 976.6(3) A(3), and Z = 4.