Tris(dithiolene) Complexes of Neodymium and Cerium: Mononuclear Species, Chains, and Honeycomb Networks
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- 作者：Mathieu Roger ; Thé ; rè ; se Arliguie ; Pierre Thué ; ry ; Marc Fourmigué ; and Michel Ephritikhine
- 刊名：Inorganic Chemistry
- 出版年：2005
- 出版时间：February 7, 2005
- 年：2005
- 卷：44
- 期：3
- 页码：584 - 593
- 全文大小：422K
- 年卷期：v.44,no.3(February 7, 2005)
- ISSN：1520-510X
文摘
Reactions of Ln(BH4)3(THF)3 (Ln = Nd, Ce) and M2dddt (M = Na, K; dddt = 5,6-dihydro-1,4-dithiine-2,3-dithiolate)in THF or pyridine gave, after addition of 18c6 (18-crown-6), several crystalline compounds which all contain thetris(dithiolene) Ln(dddt)3 unit. Crystals of [Na(18c6)(py)2]2[Na(18c6)(py)][Nd(dddt)3(py)]·3py (1·3py) are built up fromdiscrete mononuclear cationic and anionic species whereas crystals of {[Na(18c6)(py)2]0.5[Na(18c6)(py)1.5][Na1.5Nd(dddt)3]}
(2) are composed of discrete [Na(18c6)(py)x]+ cations and polymeric anionic two-dimensional layersin which the Nd(dddt)3 units are linked to three neighbors by sodium atoms to form a honeycomb network. Analysisof the temperature dependence of the molar magnetic susceptibility of 2 shows that 
MT decreases from 1.63 cm3K mol-1 at 300 K down to 0.6 cm3 K mol-1 at 5 K, due to the crystal-field splitting of the 4I9/2 free-ion state.Complexes {[Na3(18c6)1.5Nd(dddt)3(THF)]·3THF} (3·3THF) and {[K3(18c6)1.5Nd(dddt)3(py)]·3py} (4·3py) exhibitneutral polymeric layers with the Nd(dddt)3 units linked by M2(18c6) fragments. In the cerium compound{[Na2(18c6)Na(py)2Ce(dddt)3(py)]·3py} (5·3py), each Ce(dddt)3 unit is linked to two neighbors only by Na2(18c6)moieties, giving infinite zigzag chains.
(2) are composed of discrete [Na(18c6)(py)x]+ cations and polymeric anionic two-dimensional layersin which the Nd(dddt)3 units are linked to three neighbors by sodium atoms to form a honeycomb network. Analysisof the temperature dependence of the molar magnetic susceptibility of 2 shows that MT decreases from 1.63 cm3K mol-1 at 300 K down to 0.6 cm3 K mol-1 at 5 K, due to the crystal-field splitting of the 4I9/2 free-ion state.Complexes {[Na3(18c6)1.5Nd(dddt)3(THF)]·3THF} (3·3THF) and {[K3(18c6)1.5Nd(dddt)3(py)]·3py} (4·3py) exhibitneutral polymeric layers with the Nd(dddt)3 units linked by M2(18c6) fragments. In the cerium compound{[Na2(18c6)Na(py)2Ce(dddt)3(py)]·3py} (5·3py), each Ce(dddt)3 unit is linked to two neighbors only by Na2(18c6)moieties, giving infinite zigzag chains.