Incidental Polymorphism, Non-Isomorphic and Isomorphic Substitution in Calcium-Valine Coordination Polymers

Crystals

Kevin Lamberts²  Ulli Englert¹ 

[1] Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany; E-Mail

关键词: coordination polymers;    polymorphism;    isomorphism;    amino acid;    zwitterionic form;    valine;   

DOI  :  10.3390/cryst5020261

来源: mdpi

【 摘 要 】

Five coordination polymers with the stoichiometry CaX₂(valine)₂(H₂O)₂ (X = Cl, Br) were obtained from the corresponding calcium halides and either racemic and enantiopure valine. In all cases the zwitterionic amino acid is exclusively O coordinated and the halides act as counteranions for the resulting one-dimensional cationic chains. The enantiopure chloride shows dimorphism; both forms differ in connectivity from the bromide. In contrast to this structural variability for L-valine, the derivatives of the racemic amino acid are isomorphous.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.