e15 e22 [C/m21 e31 e33 W m 2 l 4 3 I601 4 1 kol AbstractA nonlinear least squares algorithm to determine the material constants of LiNbO3 from primary SAW velocity measurements is shown. If at least to some accuracy the values of the mass density p and the unclamped permittivities are known, all 13 independent elastic, piezoelectric and dielectric constants are obtained with high precision. This method is not restricted to LiNbO3 only, but can be applied to other strong coupling materials as well.