The influence of muffin tin approximation on energy band gap was studied using LMTO ASA ( Linear Muffin Tin Orbital Atomic Sphere Approximation) approach. Since the diverse data are available for LaX(X=N, P, As, ...The influence of muffin tin approximation on energy band gap was studied using LMTO ASA ( Linear Muffin Tin Orbital Atomic Sphere Approximation) approach. Since the diverse data are available for LaX(X=N, P, As, Sb), they are presented in our research as an example in order to test the reliability of our results. Four groups of muffin tin radii were chosen, they were the fitted muffin tin radii based on the optical properties of the crystals (the first), 1∶1 for La∶X(the second), 1 5∶1 for La∶X(the third), and a group of radii derived by making the charge in the interstitial space to be zero(the fourth). The results show that the fitted muffin tin radii (the first group) give the best results compared with experimental values, and the predicted energy band gaps are very sensitive to the choice of muffin tin radius in comparison with the other groups. The second and the third delivered results somewhere in between, while the fourth provided the worst results compared with the other groups. For the same crystal, with the increase of muffin tin radius of lanthanum, the calculated energy band gaps decreased, going from semi conductor to semi metal. This again clearly indicated the sensitivity of energy band structure on muffin tin approximation.展开更多
We studied the interface electronic and magnetic properties of Fe/Co deposited on Au substrate and researched the effects of roughness at the interfaces within augmented space formalism （ASF）. The full calculation i...We studied the interface electronic and magnetic properties of Fe/Co deposited on Au substrate and researched the effects of roughness at the interfaces within augmented space formalism （ASF）. The full calculation is carried out by recursion and tight-binding linear muffin tin orbital （TB-LMTO） methods. The amount of roughness is different at different atomic layers. The formalism is also applied to sharp interface, when interdiffusion of atoms is negligible. Our results of one monolayer transition metal agree with other reported results. A realistic rough interface is also modeled with three and four monolayers of transition metals, deposited on Au substrates.展开更多
文摘The influence of muffin tin approximation on energy band gap was studied using LMTO ASA ( Linear Muffin Tin Orbital Atomic Sphere Approximation) approach. Since the diverse data are available for LaX(X=N, P, As, Sb), they are presented in our research as an example in order to test the reliability of our results. Four groups of muffin tin radii were chosen, they were the fitted muffin tin radii based on the optical properties of the crystals (the first), 1∶1 for La∶X(the second), 1 5∶1 for La∶X(the third), and a group of radii derived by making the charge in the interstitial space to be zero(the fourth). The results show that the fitted muffin tin radii (the first group) give the best results compared with experimental values, and the predicted energy band gaps are very sensitive to the choice of muffin tin radius in comparison with the other groups. The second and the third delivered results somewhere in between, while the fourth provided the worst results compared with the other groups. For the same crystal, with the increase of muffin tin radius of lanthanum, the calculated energy band gaps decreased, going from semi conductor to semi metal. This again clearly indicated the sensitivity of energy band structure on muffin tin approximation.
基金Project supported by the INSPIRE Program Division,Department of Science and Technology,India
文摘We studied the interface electronic and magnetic properties of Fe/Co deposited on Au substrate and researched the effects of roughness at the interfaces within augmented space formalism （ASF）. The full calculation is carried out by recursion and tight-binding linear muffin tin orbital （TB-LMTO） methods. The amount of roughness is different at different atomic layers. The formalism is also applied to sharp interface, when interdiffusion of atoms is negligible. Our results of one monolayer transition metal agree with other reported results. A realistic rough interface is also modeled with three and four monolayers of transition metals, deposited on Au substrates.
