Showing papers by "Sven Stafström published in 1995"
TL;DR: In this article, the buckled and curved basal planes were found to have a distorted graphitel-like microstructure, and the buckling is due to the incorporation of pentagons in the basal planes, giving rise to a fullerenelike micro-structure.
Abstract: ${\mathrm{CN}}_{x}$ films were found to have a distorted graphitelike microstructure consisting of buckled and curved basal planes using high-resolution electron microscopy. Nanoindentation showed an elastic recovery of 85%, and a hardness of $\ensuremath{\sim}60$ GPa. Based on detailed quantum chemical calculations and photoelectron spectroscopy, the observed structure is proposed to consist of a network of buckled ${\mathrm{sp}}^{2}$-hybridized ${\mathrm{CN}}_{x}$ planes, cross-linked by ${\mathrm{sp}}^{3}$-hybridized bonds. The buckling is shown to be due to the incorporation of pentagons in the basal planes, giving rise to a fullerenelike microstructure.
599 citations
TL;DR: In this article, the electronic structure of a linear fullerene polymer anion was calculated based on the optimized geometry of a trimer and the band structure exhibits both non-dispersive and dispersive bands, indicating a mixture of localized and extended states.
Abstract: The electronic structure of a linear fullerene polymer anion is calculated based on the optimized geometry of a fullerene trimer. The band structure exhibits both non-dispersive and dispersive bands, indicating a mixture of localized and extended states. Two independent methods both show that the states at the Fermi energy are localized. However, there is a very narrow gap, of the order of 0.2-0.3 eV, to a dispersive unoccupied band. Taking the effects of counterions and surrounding chains into account, this gap can reduce to a pseudogap, or even disappear, which would allow for low-lying extended states and essentially metallic behaviour.
13 citations
TL;DR: In this article, the chemical and electronic structure of ultrathin molecular films of trimethylamine alane (TMAA), condensed in UHV at − 100°C, have been studied in the solid state, using both X-ray and ultraviolet photoelectron spectroscopy.
6 citations
TL;DR: In this paper, the conductance in polymeric systems of nearly macroscopic dimensions is calculated using the many-channel Buttiker-Landauer formula, and a sharp decrease in the conductivity (metal-to-nonmetal transition) is observed when the length of the polymer sample exceeds some critical value.
Abstract: The conductance in a polymeric system of nearly macroscopic dimensions is calculated using the many-channel B\"uttiker-Landauer formula. A sharp decrease in the conductivity (metal-to-nonmetal transition) is observed when the length of the polymer sample exceeds some critical value. This value defines the electron localization length. For parameters that are realistic for heavily doped trans-polyacetylene chains, the localization length is 3--4 times the average polymer chain length.
4 citations
TL;DR: The conductance in a system of coupled trans -polyacetylene chains is calculated using the many-channel Buttiker-Landauer formula and the localization properties of the soliton band are determined for a random distribution of solitons.