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Summary: In this paper, we present the first principle investigations for structural and optoelectronic properties of pure, n‐type, p‐type, and co‐doped MgSiP2 chalcopyrite compounds. To examine the structural and optoelectronic response, density functional theory (DFT) as embodied in Wien2k method is utilized. Within DFT, we have considered the exchange correlation functional prescribed by Perdew‐Burke‐Ernerhof generalized gradient approximation and Tran‐Blaha modified Becke Johnson for all computation presented in this paper. The results obtained from present calculations are in well reconciliation with previously reported experimental and theoretical data for pure compound, which affirms the accuracy of present computations. The electronic responses of all compounds are investigated through the crystal structure, energy band structure, and density of states. Optical responses of studied compounds are explained in terms of dielectric tensor, absorption, reflectivity, and refractivity spectra. Drastic change in energy band gap from pure (2.04 eV) to co‐doped compound (0.30 eV) is observed. The obtained band gaps and absorption range confirm the utility of these compounds in photovoltaic application. [ABSTRACT FROM AUTHOR]

In this paper, a systematic investigation of electronic structure and optical properties of quaternary chalcopyrite semiconductors Cu 2 ZnGeS 4 and Cu 2 ZnGeSe 4 in stannite and kesterite structures using the full-potential linearized augmented plane wave method are presented. The electronic structures and related properties of the crystals are studied with density functional theory using modified Becke – Johnson (mBJ) potential. The computed bands and density of states are found to be in good agreement with the available experimental and theoretical results. Important optical properties such as, dielectric functions, absorption spectra, refractivity and reflectivity of the crystals have also been investigated using the mBJ exchange potential. The imaginary parts of dielectric tensor are analyzed in terms of interband transitions. The band gap energies of stannite CuZnGeS 4 (CuZnGeSe 4) and kesterite CuZnGeS 4 (CuZnGeSe 4) compounds are obtained as 1.23 (0.74) eV and 1.52 (1.08) eV, respectively. Present band gap energies and optical parameters show feasibility of the studied materials in photovoltaic and other optoelectronic devices. [ABSTRACT FROM AUTHOR]

In this work, electronic structure and optical properties investigations for defect-chalcopyrite semiconductors ZnGa 2 Te 4 and CdGa 2 Te 4 are presented using full potential linearized augmented plane wave method. Energy bands and density of states (DOS) computations are performed using different flavors of exchange and correlations. The calculations are performed using Wu-Cohen generalized gradient approximation (WC-GGA), Perdew et al. (PBE-sol) and the most accurate modified Becke and Johnson (mBJ) potentials. Our investigations show that energy bands and DOS computed using mBJ potential are in better agreement with the available experimental data. Optical properties such as, dielectric tensor components, absorption spectra, reflectivity, refractivity, dielectric loss, are investigated using mBJ potential. Imaginary peaks of di-electric tensor ε 2 ( ω ) , are interpreted by means of inter-band transitions from valence to conduction band. High intensity absorption curves from 3 to 5 eV, energy band gap depicted for ZnGa 2 Te 4 (1.61 eV) and CdGa 2 Te 4 (1.78 eV) materials indicates their applicability for solar photovoltaic and other optoelectronic applications. [ABSTRACT FROM AUTHOR]

Abstract: We report energy bands, density of states and optical properties of CuGaS2 and CuInS2 chalcopyrites. The electronic structure has been computed using linear combination of atomic orbitals (LCAO) scheme within density functional theory (DFT) and full-potential linearised augmented plane wave method. The energy bands, density of states, components of dielectric tensors and absorption coefficients are compared with the available data. It is seen that the present LCAO–DFT calculations reproduce the electronic properties of both the chalcopyrites in a reasonable way. The optical properties show more absorption of solar radiations for CuGaS2 chalcopyrite, depicting its more usefulness in the solar cells. [Copyright &y& Elsevier]

Summary: In this paper, we present the first principle investigations for structural and optoelectronic properties of pure, n‐type, p‐type, and co‐doped MgSiP2 chalcopyrite compounds. To examine the structural and optoelectronic response, density functional theory (DFT) as embodied in Wien2k method is utilized. Within DFT, we have considered the exchange correlation functional prescribed by Perdew‐Burke‐Ernerhof generalized gradient approximation and Tran‐Blaha modified Becke Johnson for all computation presented in this paper. The results obtained from present calculations are in well reconciliation with previously reported experimental and theoretical data for pure compound, which affirms the accuracy of present computations. The electronic responses of all compounds are investigated through the crystal structure, energy band structure, and density of states. Optical responses of studied compounds are explained in terms of dielectric tensor, absorption, reflectivity, and refractivity spectra. Drastic change in energy band gap from pure (2.04 eV) to co‐doped compound (0.30 eV) is observed. The obtained band gaps and absorption range confirm the utility of these compounds in photovoltaic application. [ABSTRACT FROM AUTHOR]

Despite serious problems associated with toxicity of lead, lead halide perovskite based solar cells have resulted with remarkable efficiency and hence gained much interest. To overcome this aspect, numerous solutions are attempted by researchers which include the development of new environmental friendly lead free double perovskite (DP) photovoltaic materials. Enlightening on the same line, we report first principle calculations on electronic and optical properties of Cs 2 AgInCl 6 solar photovoltaic materials. Present opto-electronic computations for lead free DP compound, have been performed using the full potential linearized augmented plane wave method. In present investigations, we have adopted exchange and correlation potentials prescribed by Perdew et al. and the most accurate Tran-Blaha modified Becke-Johnson. Both exchange and correlation potential computations are performed with and without spin orbit coupling. Results obtained for electronic and optical properties are validated by systematic comparison with available experimental data. Reasonable reconciliation between investigated results and the available experimental data, endorse accuracy of present computations. To identify the effect of strain on energy gap and hence on the optical properties of Cs 2 AgInCl 6 compound, computations of electronic and optical properties have also been performed under the different values of strain application. • Computed electronic & optical properties of Cs 2 AgInCl 6 using mBJ. • Investigated the effect of strain on optoelectronic properties of compound. • Effect of SO coupling on electronic structure is also studied. • Dielectric tensor is explained in term of inter band transitions. • Based on absorption spectra, utility in Solar cell and photovoltaic is discussed. [ABSTRACT FROM AUTHOR]

In this paper, we have performed electronic and optical investigations for ternary bulk chalcopyrite's ZnGa 2 X 4 (X = S, Se) to explore their utility as solar cell materials. The electronic structure computations presented over here, revealed direct band gap for these compounds. Detailed analysis of these structural results is performed using total and partial density of states. The optical investigations such as absorption spectra, dielectric tensors, refractivity, reflectivity, energy loss and conductivity of both compounds are performed to validate their applicability for solar photovoltaic and other optoelectronic applications. The intense nature of absorption curves observed in the solar energy region (0–5 eV), supports the possible utilization of these materials for the same. All the computations are performed using the different exchange and correlation functions namely, Wu-Cohen generalized gradient approximation (WC-GGA), Perdew et al. (PBE-sol) and the most accurate modified Becke and Johnson (mBJ) potentials within the frame work of density functional theory. [ABSTRACT FROM AUTHOR]