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Dielectric anomalies of solid CO and N_2 in the audio frequency range

S. Pilla·J. A. Hamida·K. A. Muttalib·N. S. Sullivan
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Abstract

We report the first audio frequency dielectric constant measurements of CO and N_2 in their solid phases. We have observed several new features, including (1) strong hysteresis effects above an onset temperature $T_{h} \simeq 42 K$ in the β-phase of pure N_2, (2) absence of the expected short range antiferroelectric dipolar ordering in CO down to 4.2 K, and (3) anomalous temperature dependence of the dielectric constant in the α-phases of both CO and N_2. Quantum mechanical treatment of the molecular rotation explains some of the observed anomalies in the α-phase, but the strong hysteresis indicates that pure geometrical frustration plays a significant role in the β-phase.

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S. Pilla, J. A. Hamida, K. A. Muttalib, N. S. Sullivan. 1999-03-10. Dielectric anomalies of solid CO and N_2 in the audio frequency range. https://doi.org/10.1016/s0375-9601(99)00217-0

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