Crystal growth, electro-optic and electrostrictive properties of yttrium and erbium formate dihydrates, Y(HCOO)3 · 2H2O (YFD) and Er(HCOO)3 · 2H2O (ErFD)

Abstract

Abstract Large single crystals of the isotypic rare-earth formates Y(HCOO)3 · 2H2O (YFD) and Er(HCOO)3 · 2H2O (ErFD) (point group 222) were grown from aqueous solutions containing a surplus of formic acid at 70°C by controlled evaporation of the solvent. The linear electrostrictive tensor [dijk ] and the linear electro-optic tensor [rijk σ ] (unclamped) were determined at room temperature and λ = 633 nm. High anisotropy, small electro-optic constants (one tenth of corresponding values of KH2PO4) and medium electrostrictive constants (3.5 times of d 111 of α-quartz) are the main features of both formates.