Using density functional theory and quantum transport calculations based on nonequilibum Green＇s function formalism, we investigate the charge transport properties of endohedral M@C20（M = Na and K） metallofullerene...Using density functional theory and quantum transport calculations based on nonequilibum Green＇s function formalism, we investigate the charge transport properties of endohedral M@C20（M = Na and K） metallofullerenes. Our results show that the conductance of C20 fullerene can be obviously improved by insertion of alkali atom at its centre. Both linear and nonlinear sections are found on the Ⅰ-Ⅴ curves of the Au-M@C20-Au two-probe systems. The novel negative differential resistance behaviour is also observed in Na@C20 molecule but not in K@C20.展开更多
This paper uses the generalised gradient approximation based on density functional theory to analyse the geometric structure and properties of the 3d transition metal atom doped endohedral fullerene M@C20F20 （M = Sc...This paper uses the generalised gradient approximation based on density functional theory to analyse the geometric structure and properties of the 3d transition metal atom doped endohedral fullerene M@C20F20 （M = Sc-Ni）. The geometric optimization shows that the cage centre is the most stable position for M, forming the structure named as M@C20F20-4. The inclusion energy, zero-point energy, and energy gap calculations tell us that Ni@C20F20-4 should be thermodynamically and kinetically stablest. M@C20F20-4 （M = Sc-Co） possesses high magnetic moments varied from 1 to 6 μB, while Ni@C20F20-4 is nonmagnetic. The Ni-C bond in Ni@C20F20-4 contains both the covalent and ionic characters.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 10674114 and 10974078)
文摘Using density functional theory and quantum transport calculations based on nonequilibum Green＇s function formalism, we investigate the charge transport properties of endohedral M@C20（M = Na and K） metallofullerenes. Our results show that the conductance of C20 fullerene can be obviously improved by insertion of alkali atom at its centre. Both linear and nonlinear sections are found on the Ⅰ-Ⅴ curves of the Au-M@C20-Au two-probe systems. The novel negative differential resistance behaviour is also observed in Na@C20 molecule but not in K@C20.
基金Project supported by the Research Starting Foundation of Hohai University (Grant No. 2084/40801130)the Natural Science Foundation of Hohai University (Grant Nos. 2008431211 and 2008430311)+2 种基金the Excellent Innovation Personal Support Plan of Hohai Universitythe Basic Scientific Research Foundation of National Centralthe Special Foundation of the Natural Natural Science (Grant No. 10947132)
文摘This paper uses the generalised gradient approximation based on density functional theory to analyse the geometric structure and properties of the 3d transition metal atom doped endohedral fullerene M@C20F20 （M = Sc-Ni）. The geometric optimization shows that the cage centre is the most stable position for M, forming the structure named as M@C20F20-4. The inclusion energy, zero-point energy, and energy gap calculations tell us that Ni@C20F20-4 should be thermodynamically and kinetically stablest. M@C20F20-4 （M = Sc-Co） possesses high magnetic moments varied from 1 to 6 μB, while Ni@C20F20-4 is nonmagnetic. The Ni-C bond in Ni@C20F20-4 contains both the covalent and ionic characters.
