Ultrasonic measurement of the elastic constants of potassium hydrogen phthalate single crystals

Abstract

Many organic crystals with orthorhombic symmetry exhibit electro-optic, ferroelectric, and triboluminescence properties. The potassium salt of phthalic acid (KAP), with the formula C8H5O4K, finds application in soft x-ray spectroscopy due to its large d spacing and has been reported to be piezoelectric as well. KAP crystallizes into orthorhombic structure with space group Pca21 All nine elastic constants of KAP have been determined by measuring the velocity of longitudinal and transverse ultrasonic waves propagating along different symmetry directions. Velocities have been measured by the ultrasonic pulse echo overlap technique by injecting waves generated by quartz transducers through a suitable bonding medium into the crystal. The McSkimin Δt correction has been applied to determine the velocities accurately. The temperature variation of selected elastic constants over the range 300–420 K has also been measured and reported.

Synthesis, growth and characterization of a new nonlinear optical crystal sodium acid phthalate

“…Potassium acid phthalate (KAP) is one of the well-studied important NLO crystals in the phthalic acid family [8][9][10]. KAP crystal cleavage faces find applications as substrates in epitaxial techniques.…”

Potassium and ammonium hydrogen phthalates KHC6H4(COO)2and (NH4)HC6H4(COO)2- new organic crystals for Raman laser converters with large frequency shift

“…[12,13]); slow evaporation of the aqueous solution [14]; floating seed technique [15]; mercury seal technique [16]; SR method [17] Vicker's microhardness, kg mm…”

Assessment of optical, mechanical and nonlinear properties of potassium acid phthalate single crystal: a potential candidate for optoelectronic applications

“…The defect free single crystals of KAP were used as harmonic generators in the area of laser applications. Even though, many methods are available for the growth of KAP single crystals [11][12][13][14], we have adopted inexpensive SEST for the growth of bulk size single crystal of the title compound. In the current experimental study, we focus on the growth and different characterization analyses which are very important for making any suitable optical devices.…”

“…Where Pc denotes critical load at which saturation of hardness occurs and d 0 is diagonal length. Now equation(11) can be written as,…”