Elastic properties of a nematic in a tetrapalladium organyl-pentadecane system
Tóm tắt
The temperature dependences of birefringence Δn, anisotropy of permittivity ɛa, and elastic constants K
11 and K
33 in the nematic phase of a tetrapalladium organyl-pentadecane system with a pentadecane content of 55 wt % have been investigated experimentally. It has been shown that, as temperature is elevated, ɛa, K
11, and K
33 values decrease and Δn remains unchanged. Elastic constants K
11 and K
33 have been established to vary from 3.4 × 10−7 to 5.6 × 10−6 dyn and from 1.3 × 10−6 to 27.4 × 10−5 dyn, respectively. The value of ɛa has been revealed to vary over the range 0.2–0.5. It has been found that, at temperatures above the N2 → Cr phase transition by 6°C, an imposed electric field induces the growth of tetrapalladium organyl crystals.
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