- 期刊
合成兩個由檸檬酸配位基構成之鑭系錯合物及其晶體結構
Synthesis and Crystal Structures of two Lanthanide Complexes Constructed by Citrate ligand
摘要
將Ln（NO_3）_3．6H_2O（Ln = La及Nd）與檸檬酸加水混合，在pH = 2.1-2.5，溫度控制在453K下，利用水熱合成反應，得到兩個含鑭系的配位聚合物，其化學式為{[Ln（CTA）（H_2O）_2]．H_2O}_n（Ln = La（1）及Nd（2）；CTA = C（O^(-1)）（COO^(-1)）（CH_2COO^(-1)）_2）。利用X-ray晶體繞射儀、FT-IR光譜、感應耦合電漿放射光譜儀（ICP-OES）及元素分析儀測定產物晶體結構及性質。X-ray晶體繞射儀測定產物晶體結構顯示兩個配位聚合物的晶體結構相類似。CTA^(-4)分別與三個鑭系金屬配位形成七個Ln-O橋鍵，形成略為擁擠的一維（1-D）柱狀化合物。錯合物經由配位水分子及晶格水分子間的氫鍵（O-H---O）作用力，此晶體自組裝成 3-D無限延伸的網狀結構，使得此晶體更加穩定。金屬間最近距離Ln...Ln分別為4.474（1）Å錯合物1及4.390（1）Å錯合物2。
並列摘要
Two novel lanthanide metal-organic coordination polymer, {[Ln(CTA)(H_2O)_2]．H_2O}_n (Ln= La(1) and Nd(2); CTA = C(O^(-1))(COO^(-1))(CH_2COO^(-1))_2), was prepared from Ln(NO_3)_3．6H_2O (Ln=La and Nd) and citric acid at pH= 2.1-2.5 under hydrothermal condition at 453 K. The complexes were characterized by elemental analysis, inductively coupled plasma optical emission spectrometer(ICP-OES), FT-IR and X-ray crystallography. The crystal structures were determined by X-ray crystal diffraction and both of two coordination complexes are isostructural. The CTA ligand is involved in seven Ln-O bonds to three different Ln centers in a very compact 1-D pillar structure. The 1-D pillar is further connected by intermolecular hydrogen-bonding (O-H…O) to give a three-dimensional structure. The nearest Ln...Ln is 4.474(1) Å of 1 and 4.390(1) Å of 2, respectively.