Robert Waihura - Academia.edu (original) (raw)
Bit by bit into the mysteries of science have made my mind so adventurous. knowledge is power --absolute confiddence
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Lanthanum fluoride (LaF 3 ) is a rare earth metal (REM) fluoride that exists in nature as the tys... more Lanthanum fluoride (LaF 3 ) is a rare earth metal (REM) fluoride that exists in nature as the tysonite type. Pure LaF 3 crystallize into cubic, tysonite and tetragonal crystal system at different temperatures. However, it's the tysonite (hexagonal) phase is stable at room temperature. Among its key features that make LaF 3 outstanding among other similar RE compounds like La 2 O 3 are being ionic but insoluble in water or organic fluid and have a wide band gap energy about 9.0eV. These characteristics make it a potential applicant in technology revolving around optics, solid state physics and telecommunication. In the study of properties of matter, there are discrepancies between experimental and computational results of electronic and structural properties of LaF 3 . All computation calculations have been done using the Quantum ESPRESSO computer code. DFT have been implemented using ultra soft pseudo potentials and a Generalized Gradient Approximations (GGA). The Brillouin Zone (BZ) is defined by the Monkhorst-pack K mesh with 2×2×1 grid and high symmetry points used are Γ-M-K-Γ-A-L-H-A/L-M/K-H. Third order Birch-Murnghan equation of states (EOS) is used to calculate bands and density of states (DOS) using results obtained from consistent field calculations. After convergence tests, lattice constants attained are a= 7.1661Å,
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Lanthanum fluoride (LaF3) is a rare earth metal (REM) fluoride that exists in nature as the tyson... more Lanthanum fluoride (LaF3) is a rare earth metal (REM) fluoride that exists in nature as the tysonite type. Pure LaF3 crystallize into cubic, tysonite and tetragonal crystal system at different temperatures. However, it’s the tysonite (hexagonal) phase is stable at room temperature. Among its key features that make LaF3 outstanding among other similar RE compounds like La2O3 are being ionic but insoluble in water or organic fluid and have a wide band gap energy about 9.0eV. These characteristics make it a potential applicant in technology revolving around optics, solid state physics and telecommunication.
In the study of properties of matter, there are discrepancies between experimental and computational results of electronic and structural properties of LaF3. All computation calculations have been done using the Quantum ESPRESSO computer code. DFT have been implemented using ultra soft pseudo potentials and a Generalized Gradient Approximations (GGA). The Brillouin Zone (BZ) is defined by the Monkhorst-pack K mesh with 2×2×1 grid and high symmetry points used are Γ-M-K-Γ-A-L-H-A/L-M/K-H. Third order Birch-Murnghan equation of states (EOS) is used to calculate bands and density of states (DOS) using results obtained from consistent field calculations. After convergence tests, lattice constants attained are a= 7.1661Å, c=7.3094Å and c/a=1.02 against a= 7.260Å, c= 6.6Å [6] from WIEN2K, and a=7.427Å, c= 7.329Å of CASTEP [13]. The calculated band gap proves that LaF3 is a wide direct band gap material with a band gap energy = 8.4066 eV against experimental 9.4ev and computed 7.74eV.
Lanthanum fluoride (LaF 3 ) is a rare earth metal (REM) fluoride that exists in nature as the tys... more Lanthanum fluoride (LaF 3 ) is a rare earth metal (REM) fluoride that exists in nature as the tysonite type. Pure LaF 3 crystallize into cubic, tysonite and tetragonal crystal system at different temperatures. However, it's the tysonite (hexagonal) phase is stable at room temperature. Among its key features that make LaF 3 outstanding among other similar RE compounds like La 2 O 3 are being ionic but insoluble in water or organic fluid and have a wide band gap energy about 9.0eV. These characteristics make it a potential applicant in technology revolving around optics, solid state physics and telecommunication. In the study of properties of matter, there are discrepancies between experimental and computational results of electronic and structural properties of LaF 3 . All computation calculations have been done using the Quantum ESPRESSO computer code. DFT have been implemented using ultra soft pseudo potentials and a Generalized Gradient Approximations (GGA). The Brillouin Zone (BZ) is defined by the Monkhorst-pack K mesh with 2×2×1 grid and high symmetry points used are Γ-M-K-Γ-A-L-H-A/L-M/K-H. Third order Birch-Murnghan equation of states (EOS) is used to calculate bands and density of states (DOS) using results obtained from consistent field calculations. After convergence tests, lattice constants attained are a= 7.1661Å,
Lanthanum fluoride (LaF3) is a rare earth metal (REM) fluoride that exists in nature as the tyson... more Lanthanum fluoride (LaF3) is a rare earth metal (REM) fluoride that exists in nature as the tysonite type. Pure LaF3 crystallize into cubic, tysonite and tetragonal crystal system at different temperatures. However, it’s the tysonite (hexagonal) phase is stable at room temperature. Among its key features that make LaF3 outstanding among other similar RE compounds like La2O3 are being ionic but insoluble in water or organic fluid and have a wide band gap energy about 9.0eV. These characteristics make it a potential applicant in technology revolving around optics, solid state physics and telecommunication.
In the study of properties of matter, there are discrepancies between experimental and computational results of electronic and structural properties of LaF3. All computation calculations have been done using the Quantum ESPRESSO computer code. DFT have been implemented using ultra soft pseudo potentials and a Generalized Gradient Approximations (GGA). The Brillouin Zone (BZ) is defined by the Monkhorst-pack K mesh with 2×2×1 grid and high symmetry points used are Γ-M-K-Γ-A-L-H-A/L-M/K-H. Third order Birch-Murnghan equation of states (EOS) is used to calculate bands and density of states (DOS) using results obtained from consistent field calculations. After convergence tests, lattice constants attained are a= 7.1661Å, c=7.3094Å and c/a=1.02 against a= 7.260Å, c= 6.6Å [6] from WIEN2K, and a=7.427Å, c= 7.329Å of CASTEP [13]. The calculated band gap proves that LaF3 is a wide direct band gap material with a band gap energy = 8.4066 eV against experimental 9.4ev and computed 7.74eV.