Non-linear optical response of rutile-related oxides, LiM V M VI O6, and their derivatives obtained by ion-exchange and intercalation

Abstract
Polycrystalline samples of oxides of the general formula LiMVMVIO6(MV= Nb, Ta; MVI= Mo, W), crystallizing in a non-centrosymmetric (space group P21m) trirutile structure, exhibit second harmonic generation (SHG) of 1064 nm radiation with efficiencies 15–45 times that of α-quartz; interestingly, the SHG response is retained by the protonated derivatives HMVMVIO6·xH2O, and their n-alkylamine intercalates as well.