Abstract
Ultrasonic, piezoelectric and dielectric measurements on single crystals of (–)-2-a-α-methylbenzylamino-5-nitropyridine (MBANP) are reported. Longitudinal and transverse velocity measurements in six crystal directions were used to calculate the 13 elastic constants. Dielectric measurements were carried out in four directions and compared with refractive index measurements carried out at optical frequencies. MBANP exhibited piezoelectric coefficients of similar magnitude to those found in lithium niobate. These data are discussed in terms of the intermolecular interactions occurring in the crystal structure.