A first-principles investigation of the electronic, elastic, piezoelectric and acoustic properties of K3B6O10Cl

Distorted perovskite crystals can lead to large second harmonic responses. K3B6O10Cl is a recently synthesized perovskite-like crystal that exhibits a large second harmonic response. A first-principles investigation of the electronic properties, elastic constants and piezoelectric properties of this newly synthesized material is presented. These calculation results are used to calculate the physical properties of K3B6O10Cl, which include its Young’s modulus, Poisson ratio, velocity of acoustic waves, and Debye temperature. K3B6O10Cl has a direct band gap of 5.16 eV. The calculated non-zero piezoelectric constants of K3B6O10Cl suggest that K3B6O10Cl is a good piezoelectric material. Using the calculated elastic and piezoelectric constants, the slowness surface of acoustic waves is derived within the framework of the quasistatic approximation. The results calculated can be used to assess the use of K3B6O10Cl as a potential nonlinear optical material.