The α-β phase transition in solid oxygen
The α-β phase transition in solid oxygen
复制标题
固体氧中的α-β相变
DOI：
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发表时间：
1987
期刊：
影响因子：
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通讯作者：
R. Meier
中科院分区：
文献类型：
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作者：
B. Kuchta;T. Luty;R. Meier
分析了决定固体氧中α - β相变机理和温度的两个重要因素：提高相变温度的磁弹性耦合和在低温下稳定α - β相的反铁磁序，从而降低了相变点。磁性力和弹性力之间的竞争导致了晶体的不稳定性，从而导致了相变。用耦合磁化率法分析了α相的稳定极限，并从测量的磁化率推导出α相的稳定极限。得出的结论是，极低的相变温度（与α相的尼尔温度相比）是β相的短程反铁磁有序的结果。进一步证明了α - β跃迁明显是一阶跃迁。
Two important factors that determine the mechanism and temperature of the alpha - beta phase transition in solid oxygen are analysed: the magneto-elastic coupling which increases the temperature of the transition, and the antiferromagnetic order in the beta -phase which stabilises this phase at low temperatures, thus lowering the transition point. It has been shown that the competition between magnetic and elastic forces leads to an instability of the crystal and, consequently, to the phase transition. The stability limit of the beta -phase is analysed within the coupled-susceptibility approach, and the stability of the alpha -phase is deduced from measured magnetic susceptibility. It is concluded that the very low temperature of the phase transition (as compared with the Neel temperature of the alpha -phase) is a consequence of the short-range antiferromagnetic order in the beta -phase. Furthermore, it is shown that the alpha - beta transition is clearly of first order.