Dra Marbella Calvino Gallardo

@article{BERMEOCAMPOS2023157481,

title = {Surface morphology effects on the mechanical and electronic properties of halogenated porous 3C-SiC: A DFT study},

author = {R. Bermeo-Campos and K. Madrigal-Carrillo and S. E. Perez-Figueroa and M. Calvino and A. Trejo and F. Salazar and A. Miranda and M. Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S0169433223011595},

doi = {https://doi.org/10.1016/j.apsusc.2023.157481},

issn = {0169-4332},

year  = {2023},

date = {2023-01-01},

journal = {Applied Surface Science},

volume = {631},

pages = {157481},

abstract = {Silicon carbide nanostructures have been widely studied due to their potential technological applications. However, the theoretical characterization, especially the effect of the surface on the mechanical properties of this material is still underexplored. In this work, we report the electronic and mechanical properties of 3C-SiC nanopores with different pore surfaces and different passivation schemes using a density functional theory approach and the supercell technique. The nanopores were modeled by removing columns of atoms in the [001] direction, thus creating four types of pores, two with an Only C or Si pore and two with a C or Si-Rich pore surface. All surfaces were passivated with hydrogen, then some atoms of H were replaced with fluorine and chlorine. Results show that pores with a higher concentration of C on the surface have a larger bandgap compared with the Si cases. Moreover, only a few changes can be observed due to passivation. For the mechanical properties the Bulk and Young’s modulus were calculated and show that the Only C structures were the most brittle and, for almost all the pores, the H + Cl passivation improve the Bulk modulus.},

keywords = {DFT, electronic properties, Halogens, Mechanical properties, Porous SiC},

pubstate = {published},

tppubtype = {article}

}

@article{CUEVAS2022115372,

title = {Theoretical approach to the phonon modes of GaSb nanowires},

author = {J. L. Cuevas and M. Ojeda and M. Calvino and A. Trejo and F. Salazar and A. Miranda and L. A. Perez and M. Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S1386947722002077},

doi = {https://doi.org/10.1016/j.physe.2022.115372},

issn = {1386-9477},

year  = {2022},

date = {2022-01-01},

journal = {Physica E: Low-dimensional Systems and Nanostructures},

volume = {143},

pages = {115372},

abstract = {Gallium Antimonide nanowires (GaSbNWs) have attracted much attention due to their possible applications in mid infrared detectors, however, there are only few theoretical investigations about this material and almost none regarding its vibrational properties. In this work the phonon modes of GaSbNWs were studied using the density functional theory with the finite displacement supercell scheme. The nanowires are modeled by removing atoms outside from a circumference along the [1 1 1] direction. All surface dangling bonds were passivated with hydrogen atoms. The results show that the expected red-shift of the highest frequency modes of GaSb are hindered by low frequency H bond bending modes. Three clearly distinguishable frequency intervals were observed: One with vibrations whose main contribution come from the Ga and Sb nanowire atoms, the second interval with main contributions from H bending modes and finally a high frequency interval where the main contributions come from H stretching modes. Also, it was observed that the radial breathing mode (RBM) decreases when the nanowire diameter increases, while the contrary tendency is observed with their specific heat (the specific heat increases as the nanowire diameter increases), except in the low temperature region where the lower diameters have higher specific heat values. These results could be important for the characterization of these nanowires with IR and Raman techniques.},

keywords = {DFT, Gallium Antimonide, Nanowires, Phonons},

pubstate = {published},

tppubtype = {article}

}