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Electron drift mobilities μe and electron–ion recombination rate constants kr in gaseous, liquid, and solid argon have been measured by the analysis of transient current induced with the irradiation of an x-ray pulse as functions of temperature and external electric field strength except solid. The effect of external dc electric field on kr up to ∼3×10−3 Td (1 Td=10−17 V cm2/molecule) was examined in gaseous and liquid phases. The observed kr values in both liquid and gas phases were found to be much smaller than those calculated by the reduced Debye equation. The deviation, which is bigger in gas than in liquid, has been compared with recent theoretical studies1–5 which were presented to explain our previous data on the kr values for methane.6 It has been concluded that the recombination also in liquid and gaseous argon is not a usual diffusion-controlled reaction. In the solid phase the observed kr values were almost in agreement with those calculated by the reduced Debye equation. The electron–ion recombination rate constants in both liquid and gas phases increased almost linearly with an external dc electric field up to a critical electric field strength below which electron mobility was nearly constant, and decreased with further increase in the electric field where electron mobility also decreased.

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Some new examples of injected smectic behaviour for binary mixtures of strong terminally polar mesogens (CBs, PCHs, BCOs, and CCHs) with a range of terminally non-polar esters are presented. Variations in the strength of thc injected behaviour are discussed. Examples of S, as well as S , injection occur.Studies of mixtures of terminally non-polar 4,4-dialkyl-2'-fluoro-p-terphenyls (I) with cyano-substituted mesogens are also described and provide an example of injection of S , and S , phases.O f greater interest is the observation that binary mixtures consisting solely of homologues of (I) can exhibit reentrant nematic behaviour, providing further evidence that reentrant phenomena are not a special feature of terminally polar mesogens and their mixtures. An isomeric mixture of two compounds of structure (1) also gives an interesting case of an injected S, phase. and enhanced S, properties are recorded for other mixtures of homologues of (I).Mixtures involving alkylialkoxy analogues of (I) also provide cxamples of S,. phase injection or enhancemcnt, and in one case some evidence for injected S, behaviour.