| Journal: | Revista mexicana de física |
| Database: | PERIÓDICA |
| System number: | 000378502 |
| ISSN: | 0035-001X |
| Authors: | Quintero, M1 Marquina, J1 Quintero, E1 Moreno, E1 Alvarez, S1 Rincón, C1 Grima, P1 Bocaranda, P1 Rivero, D1 Henao, J.A2 Macías, M.A2 |
| Institutions: | 1Universidad de Los Andes, Facultad de Ciencias, Mérida. Venezuela 2Universidad Industrial de Santander, Facultad de Ciencias, Bucaramanga, Santander. Colombia |
| Year: | 2014 |
| Season: | Mar-Abr |
| Volumen: | 60 |
| Number: | 2 |
| Pages: | 168-175 |
| Country: | México |
| Language: | Inglés |
| Document type: | Artículo |
| Approach: | Analítico, teórico |
| English abstract | Room temperature X-ray powder diffraction measurements were carried out on nine polycrystalline samples of the Cu2BII CIVX4 (B=Mn, or Fe, or Co; C=Si, or Ge, or Sn; X=S, or Se, or Te) magnetic semiconductor compounds. The diffraction patterns were used to show the equilibrium conditions and to derive crystalline parameter values. The results showed that four of these compounds have a tetragonal stannite structure with space group 142m(N° 121), two an orthorhombic wurtz-stannite structure with space group Pmn21(N° 31) and three of them an orthorhombic pseudo-cubic structure with space group F222 (N° 22). In each case, the structure was refined using the Rietveld method. When the obtained atomic parameter values for the tetragonal compounds were plotted as a function of molecular weight W, it was found that the values of the atomic positions, the cation-anion bond distances, tetragonal distortion and internal distortion of the compounds containing S and/or Se lay on different lines. Also, it was found that when the experimental points of the cation-anion bond distances dCu-VI, dII-VI and dIV-VI were plotted against the effective lattice parameter ae = (V/N)1/3, a linear variation of these distances with ae was obtained. Values of the ionic energy gap Ci and homopolar energy gap Eh using the Phillips-Van Vechten scheme, with the present experimental crystallographic results as well as using the atomic data, were determined. It was found that the observed and predicted values of Ci and Eh lie on the same straight line |
| Disciplines: | Física y astronomía |
| Keyword: | Física de materia condensada, Semiconductores, Estructura cristalina, Difracción de rayos X, Refinamiento de Rietveld, Crecimiento de cristales |
| Keyword: | Physics and astronomy, Condensed matter physics, Magnetic semiconductors, Crystal structure, X-ray diffraction, Rietveld refinement, Crystal growth |
| Full text: | Texto completo (Ver PDF) |
