Crystal growth,crystal structure and physical properties of polar orthorhombic tris(glycine) zinc chloride

Large single crystals of the polar (point group mm 2) compound tris(glycine) zinc chloride, (NH₃CH₂COO)₃ · ZnCl₂, were grown from aqueous solutions. The refractive indices were measured in the wavelength region from 365 nm to 1083 nm and an unpolarised absorption spectrum was recorded (transparency range from 260 to 1550nm). The phase matching conditions for second harmonic generation were analysed: both, type I (ss‐f) and type II (sf‐f) are possible in the red and near IR region. All five components of the piezoelectric tensor [d_ijk ] were determined; the maximum values of longitudinal and transverse piezoelectric effects are less than one half of d₁₁₁ of α‐quartz. In addition, a redetermination of the crystal structure (including location of H atoms) is presented. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)