Linear electro-optical properties of orthorhombic KNbO3

Linear optical susceptibility and clamped linear electro-optical tensor coefficients of orthorhombic KNbO3 are calculated using a formalism based on bond charge theory. Calculated values are in close agreement with experimental data. The covalent Nb–O bonds constituting distorted NbO6 octahedral groups are found to be the major contributors making these groups more sensitive than KO12 groups to electro-optic coefficients.