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Journal of thermal analysis

, Volume 25, Issue 2, pp 525–529 | Cite as

Fusion temperatures of rare earth metal trihalides

  • I. A. Kahwa
Article

Abstract

The fusion temperatures (Tf) of rare earth metal trihalides LnX3 (Ln=La−Lu, Y; X=Cl, Br, I) typically decrease to a minimum, before taking on an upward trend as the ionic radius of Ln3+ decreases. This trend is associated with the variations in the energetic stability of the coordination polyhedron around Ln3+. A good correlation is obtained between the variations in the energetic stability of the crystal structure of LnX3 andTf.

Keywords

Polymer Physical Chemistry Crystal Structure Inorganic Chemistry Rare Earth 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Zusammenfassung

Die Schmelztemperaturen (Tf) der Trihalide der Seltenen Erdmetalle LnX3 (Ln=La-Lu, Y; X=Cl, Br, J) gehen mit abnehmendem Ionenradius von Ln3+ auf typische Weise durch ein Minimum. Dieser Trend wird mit den Unterschieden in der energetischen Stabilität der um das Ln3+-Ion angeordneten Koordinationspolyeder in Verbindung gebracht. Es wurde eine gute Korrelation zwischen der energetischen Stabilität der Kristallstruktur undTf erhalten.

Резюме

Температуры плавлен ия трехгалоидных соединений редкозем ельных элементов LnX3 (Ln=La-Lu,Y; Х=Сl,Вг, I) сначала умен ьшаются до минимума п еред тенденцией к увеличению с уменьш ением ионного радиус а редкоземельных элем ентов. Такая тенденци я связана с изменением энергетической усто йчивости координационного по лиэдра вокруг Ln3+. Получена хор ошая корреляция межд у изменением энергети ческой устойчивости кристаллических стр уктур LnX3 и их температу рами плавления.

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Copyright information

© Wiley Heyden Ltd., Chichester and Akadémiai Kiadó, Budapest 1982

Authors and Affiliations

  • I. A. Kahwa
    • 1
  1. 1.Chemistry DepartmentUniversity of Dar es SalaamDar es SalaamTanzania

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