Intercalation into carbons with varying degree of graphitisation

摘要: In their beginnings, researches on physical properties of lamellar intercalation compounds graphite indicated parallels with charge transfer between the same electron donor or acceptor partners, and smaller aromatic molecules. Charge bonds in are often only weak. However, a large increase electrical conductivity is found all cases, compared component substances. Graphite can be likened to semi-conductors zero energy gap. Modern band theories which aim at precise calculations (including those compounds) assume fractional partner molecules from carbon hexagon layers. This fraction may quite small, though unit has been assumed class contain macro-anions formed by electrochemical oxidation. Recent work, e.g., optical intercalated halogens such as bromine, indicates (in this case) few tenths one percent. Various considerations suggest that very high parallel layers, for so many compounds, must associated an exceptionally mobility layer planes “charges transferred”. To achieve optimum synthetic metals, factors reduce suppressed reduced various ways. These include thermal scattering well diverse defects graphite. Increasing separation layers binary useful device. Use well-oriented graphites quality seems essential. Properties ‘low scatter’ conductors urgently call further research have discussed. They evaluation relationships conductivities (the Wiedemann-Franz ratio). At right angles little systematic information yet available about significant expansion. We need know, too, anisotropy resistance its temperature coefficient, thermo-electric power. Within each ‘ripple potential’ restricts lateral displacements intercalate surprisingly smooth. Two-dimensional mobilities accordingly three-dimensional ordinary solids. Under favorable circumstances, metals whose surpass best natural defect-free copper silver now readily prepared. order measure properties, some novel, it important extend measurements (possibly critical) current densities. meet Pulse Meter devised constructed present performance gives us densities up 40 000 A/cm2 pulse durations rest periods pulses variable will. being used help elucidating remarkable metals.