Raman spectra and lattice vibrations in single crystals of potassium acid phthalate

Abstract

Raman scattering from single crystals of potassium acidphthalate has been observed with the 4880 di and 5145 di excitations of an argon ion laser. The room temperature Raman spectra, recorded with a Jarrel-Ash spectrometer, in the region 0-300 cm-', exhibit broad bands which are attributed to the translatory and rotatory types of lattice vibrations of the potassium and acid phthalate ions in the crystal. Experiments were carried out at 77 K using a Spex double monochromator and the Raman scattering in the second-order of the gratings were observed. The result was a splitting of the several broad bands into their components. Assignments of these low frequency Raman spectra, consistent with the crystal structure and the group theoretical predictions is given. Variations in intensities of some of the spectra due to crystal orientation are also observed and briefly discussed.

Combustion synthesis and characterization of NiO nanoparticles

“…5 The Raman spectra of N 105 and N 11 are identical and consist of well-defined bands which originate due to disorder induced one-phonon scattering (1P) TO (Transverse Optical) at 452 cm À 1 and LO (Longitudinal Optical) at 577 cm À 1 modes, two-phonon scattering (2P) 2 TO at 741 cm À 1 , TOþLO at 922 cm À 1 and 2LO at 1119 cm À 1 and a two magnon scattering (2 M) band at around 1400 cm À 1 [57]. The peak below 200 cm À 1 can be assigned to lattice vibrations [58]. The optical absorption spectra of NiO NPs are shown in Fig.…”

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

“…g) Under nanosecond (65 ns) radiation of Q-switched Nd 3+ :Y3Al5O12 laser at λ ≈ 1.064 μm and repetition rate 10 KHz [22]. h) From FT-IR spectra [23] and spontaneous Raman scattering spectra [24]. Table 2 Some physical properties of orthorhombic KHC6H4(COO)2 single crystal at room temperature (units of all properties given as in original papers) of crystalline mica (KMg 3 Si 3 AlO 10 F 2 ).…”

“…g) Under nanosecond (65 ns) radiation of Q-switched Nd 3+ :Y 3 Al 5 O 12 laser at λ ≈ 1.064 µm and repetition rate 10 KHz [22]. h) From FT-IR spectra [23] and spontaneous Raman scattering spectra [24].…”