Relationship of crystallographic polarity to piezoelectric, pyroelectric and chemical etching in Li₂GeO₃ and LiGaO₂ single crystals

Absolute assignment of the atomic planes of Li₂GeO₃ and LiGaO₂ is made by ion surface scattering (ISS) and the crystallographic polarity is defined. Pyroelectric coefficients p₃ and the piezoelectric constants d₃₃ of lithium metagermanate and lithium gallate are determined. Pyroelectric and piezoelectric coefficient signs when defined on the crystallographic sign convention of the axes are negative and positive, respectively. The results are correlated with chemical etching studies.