Abstract

The low-temperature behavior of the heat capacity and photoluminescence of the earlier structurally characterized binuclear pivalate complex [Eu₂(Bath)₂(Piv)₆] (monoclinic crystal system, I2/a) (I), where Bath = 4,7-diphenyl-1,10-phenanthroline, Piv = \({{{\text{(C}}{{{\text{H}}}_{{\text{3}}}}{\text{)}}}_{{\text{3}}}}{\text{CCO}}_{2}^{ - }\), is studied. The temperature dependence of the heat capacity in a temperature range of 5.96–302.88 K is measured by adiabatic calorimetry, and the thermodynamic functions \(C_{p}^{^\circ }\)(T), S°(T), Ф°(Т), and Н°(Т) – Н°(0) are calculated. The absence of low-temperature phase transitions in complex I is shown. In a temperature range of 98–295 K, complex I demonstrates a high temperature stability of the integral photoluminescence intensity of the ⁵D₀–⁷F_j (j = 0–6) transitions of the Eu³⁺ ion.

中文翻译：

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双核新戊酸配合物 [Eu2(Bаth)2(Piv)6] 的热容量和光致发光的低温行为

摘要

早期结构表征的双核新戊酸配合物[Eu₂(Bath)的低温热容和光致发光行为₂(Bath)]（单斜晶系，₆(Piv)₂2/a) (I\(C_{p}^{^\circ }\)< /span>) 和 Н<计算/span>离子。³⁺ = 0–6) Eu 的跃迁j (_jF⁷–₀D⁵表现出I 中不存在低温相变。在98–295 K的温度范围内，配合物I°(0)。复合物 ) – Т°(НТ)、Ф°(T° (S), T(，已研究。通过绝热量热法测量了 5.96–302.88 K 温度范围内热容的温度依赖性，热力学函数\({{{\text{(C}}{{{\文本{H}}}_{{\text{3}}}}{\text{)}}}_{{\text{3}}}}{\text{CCO}}_{2}^{ - }\))，其中 Bath = 4,7-二苯基-1,10-菲咯啉，Piv =