Carbons as a route to synthetic metals
β Scribed by A.R Ubbelohde
- Publisher
- Elsevier Science
- Year
- 1976
- Tongue
- English
- Weight
- 667 KB
- Volume
- 14
- Category
- Article
- ISSN
- 0008-6223
No coin nor oath required. For personal study only.
β¦ Synopsis
From itb crystal structure~graphite must be considered a5 a solid organic compound containing macroaromatic molecules and deiocalised electrons. A hypothesis that intercalation crystal compounds of graphite are analogous in quantum chemistry with charge transfer compounds formed between smaller aromatic hyntems. and electron donor or electron acceptor molecules, has been abundantly verified experimentally. A great diversity of intercalation compounds of graphite has been prepared in polycrystalline compact or powdered form. All show much higher electrical c~~nductivity than the parent graphite. with p or n carriers predominant according to the electron acceptor or electron donor character of the intercaiate. Graphite exhibits extremely high anisotropy in its crystal structure and its physical properties. Much of this anisotropy persists in synthetic metals prepared from graphite by intercalation. This make5 it essential to start with well oriented graphite in large pieces, to evaluate intrinsic electronic properties in the principal crystal directions with precision, Progressive advances are described in high temperature chemical engineering of graphite, whose final outcome has been the successful production of large pieces of well oriented material. Some of these novel procedures are also of interest, e.g. in the chemical engineering production of diamond from graphite. Using such well oriented materials, experimental study of intercalation (charge transfer) compounds has become much more precise. Some challenging problem\ have been revealed concerning the anisotropy of electronic properties. In general. conduction of electricity in the basal plane directions follows patterns familiar with other metals. But at right angle5. unusual hehaviour i$ ,ipparent particularly at low temperature.
π SIMILAR VOLUMES
## Abstract For Abstract see ChemInform Abstract in Full Text.
## Abstract Starting from ethyl 2βcyclohexenβ1βcarboxylate (**3**) the total synthesis of the perhydrohistrionicotoxin intermediate **23** was achieved in 25% overallβyield. The two key steps involve a positionally specific addition of HOBr to the oximeβolefin **7** and the alkylation of bromooxime