A theoretical study of the oxygen K-edge near-edge X-ray absorption fine structure of N2O/Ir（110）

A multiple-scattering cluster method is employed to calculate the oxygen K-edge near-edge X-ray absorption fine structure of N2O/Ir(110) and its monolayer. Two peaks and one weak resonance appear in both cases. The self-consistent field DV-Xα calculations of the peaks and resonance show that the physical origin of the pre-edge peak x is different from those of the main peak 1 and the other weak resonance σ 1 . This setup is intrinsic to the N2O monolayer, owing to the interaction between the neighbouring molecular chains in the monolayer and partly to the adsorbed atomic oxygen, according to both the theoretical and experimental data.     

Evidence for change of the interfacially local structure of titanium oxide／bis[（4,4’—carboxy—2,2’—bipyridine）（thiocyanato）]ruthenium nanocomposite^＋

Tianium oxide/bis[(4，4’-carboxy-2,2’-bigyridine)(thiocyanato)]ruthenium(cis-(NCS)2RuL2)nancomposites were prepared by the self-assembly method.In this system,their interfacially local structures were probed by x-ray absorption spectroscopy (XAS)and the Ti-O interatomic distance and the coordination number of the O atoms around the Ti central atoms were extracted.Copared with TiO2 annoparticles,the Ti local structure in the nanocomposite was changed,Which is responsible for binding cis(NCS)2RuL2 to the surface of TiO2 nanoparticles.copyright 2001 John Wiley and Sons,Ltd.     

Comparative study of the electrical properties of Au/n-Si （MS） and Au/Si3N4/n-Si （MIS） Schottky diodes

In this paper,the electrical parameters of Au/n-Si(MS) and Au/Si3N4/n-Si(MIS) Schottky diodes are obtained from the forward bias current-voltage(I-V) and capacitance-voltage(C-V) measurements at room temperature.Experimental results show that the rectifying ratios of the MS and MIS diodes at±5 V are found to be 1.25 × 103 and 1.27 × 104,respectively.The main electrical parameters of the MS and MIS diodes,such as the zero-bias barrier height(ΦBo) and ideality factor(n),are calculated to be 0.51eV(I-V),0.53eV(C-V),and 4.43,and 0.65eV(I-V),0.70eV(C-V),and 3.44,respectively.In addition,the energy density distribution profile of the interface states(Nss) is obtained from the forward bias I-V,and the series resistance(Rs) values for the two diodes are calculated from Cheung's method and Ohm's law.     

Density functional calculations on the geometric structure and properties of the 3d transition metal atom doped endohedral fullerene M@C20F20（M=Sc-Ni）

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@C 20 F 20-4.The inclusion energy,zero-point energy,and energy gap calculations tell us that Ni@C 20 F 20-4 should be thermodynamically and kinetically stablest.M@C 20 F 20-4(M = Sc-Co) possesses high magnetic moments varied from 1 to 6 μ B,while Ni@C 20 F 20-4 is nonmagnetic.The Ni-C bond in Ni@C 20 F 20-4 contains both the covalent and ionic characters.