Far-infrared lattice vibration spectra of copper gallium (indium) ternary selenides (tellurides): A consequence of trivalent cation and anion interrelation

2017-01-01
Experimental spectra for copper gallium (indium) ternary selenides (tellurides) crystals, measured in the 50-500 cm(-1) frequency range, revealed four infrared-active modes. Spec tral dependencies of refractive index and absorption coefficient were computed from reflectivity experiments. The frequencies of optical modes, damping constants and oscillator strengths were also evaluated. The bands observed in IR spectra were provisionally attributed to various vibration types (valence and valence-deformation). Crystal structure and atomic composition ratio of the constituent elements in Cu3Ga5Se9, Cu3In5Se9 and Cu3In5Te9 crystals were revealed from structural characterization techniques of X-ray diffraction and energy dispersive spectroscopy. (C) 2017 Elsevier GmbH. All rights reserved.

Suggestions

Interrelation of vibrational spectra of Ag3Ga5Se9, Ag3Ga5Te9 and Ag3In5Te9 single crystals: A consequence of trivalent cation and anion substitutions
Hasanlı, Nızamı (2017-09-01)
Silver gallium (indium) ternary selenides (tellurides) single crystals were studied through infrared reflection in the frequency range of 80-500 cm(-1). These spectra presented four infrared-active modes for studied crystals. Spectral dependencies of optical constants were computed from reflectivity spectra. The frequencies of transverse and longitudinal optical modes, damping constants and oscillator strengths were also evaluated. By replacing light selenium anions by heavier tellurium ones in Ag3Ga5Se9 cr...
Temperature-dependent optical properties of GaSe layered single crystals
Hasanlı, Nızamı (2016-8-01)
Optical properties of GaSe single crystals have been investigated using temperature-dependent transmission and room temperature reflection measurements in the wavelength range of 380–1100 nm. The analysis of the absorption data at room temperature showed the existence of indirect transitions in the crystal with energy band gap of 1.98 eV. Temperature dependence of the transmission measurements revealed the shift of the absorption edge toward lower energy as temperature is increased from 10 to 280 K. The rat...
Temperature-dependent optical properties of GaSe layered single crystals
IŞIK, MEHMET; TUĞAY, EVRİN; Gasanly, N. M. (2016-01-01)
Optical properties of GaSe single crystals have been investigated using temperature-dependent transmission and room temperature reflection measurements in the wavelength range of 380-1100nm. The analysis of the absorption data at room temperature showed the existence of indirect transitions in the crystal with energy band gap of 1.98eV. Temperature dependence of the transmission measurements revealed the shift of the absorption edge toward lower energy as temperature is increased from 10 to 280K. The rate o...
Long-wavelength lattice vibrations of Ag3In5Se9 and Ag3In5Te9 single crystals: An inversion of LO- and TO-mode frequencies
Hasanlı, Nızamı (2016-07-10)
Infrared (IR) reflectivities are registered in the frequency range of 50-2000 cm(-1) for Ag3In5Se9 and Ag3In5Te9 single crystals grown by Bridgman method. Three infrared active modes are detected in spectra. The optical parameters, real and imaginary parts of the dielectric function, the function of energy losses, refractive index, absorption index and absorption coefficient were calculated from reflectivity experiments. The frequencies of transverse and longitudinal optical modes (TO and LO modes) and osci...
Near-infrared photoluminescence and thermally stimulated current in Cu3Ga5Se9 layered crystals: A comparative study
Hasanlı, Nızamı (2016-07-01)
Near-infrared photoluminescence (PL) and thermally stimulated current (TSC) spectra of Cu3Ga5Se9 layered crystals grown by Bridgman method have been studied in the photon energy region of 1.35-1.46 eV and the temperature range of 15-115 K (PL) and 10-170 K (TSC). An infrared PL band centered at 1.42 eV was revealed at T = 15 K. Radiative transitions from shallow donor level placed at 20 meV to moderately deep acceptor level at 310 meV were suggested to be the reason of the observed PL band. TSC curve of Cu3...
Citation Formats
N. Hasanlı, “Far-infrared lattice vibration spectra of copper gallium (indium) ternary selenides (tellurides): A consequence of trivalent cation and anion interrelation,” OPTIK, pp. 19–25, 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/37632.