Thursday, November 29, 2012

l- and d-[Ln(HCO2)(SO4)(H2O)]n (Ln = La, Ce, Pr, Nd, and Eu): Chiral Enantiomerically 3D Architectures Constructed by Double −[Ln–O]n– Helices


l- and d-[Ln(HCO2)(SO4)(H2O)]n (Ln = La, Ce, Pr, Nd, and Eu): Chiral Enantiomerically 3D Architectures Constructed by Double −[Ln–O]n– HelicesAbstract Image

29/septiembre/2012
Paulina Levario

A total of 10 three-dimensional chiral coordination compounds l- and d-[Ln(HCO2)(SO4)(H2O)]n (Ln = La, Ce, Pr, Nd, and Eu) have been synthesized without any chiral auxiliary and characterized by IR, thermogravimetric, and elemental analyses. Their structures were determined by single-crystal X-ray structural analysis, which shows that l-[Ln(HCO2)(SO4)(H2O)]n (Ln = La, Ce, Pr, Nd, and Eu) crystallize in space group P43 and are laevogyrate and isostructural. The chiral frameworks of l-[Ln(HCO2)(SO4)(H2O)]n are constructed from l-helical Ln–O cluster chains, while adjacent l-type helical −[Ln–O]n– chains are connected through O–Ln–O linkages to form chiral intertwined Ln–O double helices of left-handedness.d-[Ln(HCO2)(SO4)(H2O)]n crystallize in space group P41, and their chiral frameworks consist of d-helical Ln–O cluster chains. The observed second-harmonic-generation efficiencies of [La(HCO2)(SO4)(H2O)]n, Ce(HCO2)(SO4)(H2O)]n, [Pr(HCO2)(SO4)(H2O)]n, [Nd(HCO2)(SO4)(H2O)]n, and [Eu(HCO2)(SO4)(H2O)]n are 0.7, 0.8, 0.7, 0.5, and 0.7 times that of urea, respectively. It is particularly interesting that [Pr(HCO2)(SO4)(H2O)]n shows good two-photon absorption.

Para mayor información:

l- and d-[Ln(HCO2)(SO4)(H2O)]n (Ln = La, Ce, Pr, Nd, and Eu): Chiral Enantiomerically 3D Architectures Constructed by Double −[Ln–O]n– Helices

Weiwei Ju, Deng Zhang, Dunru Zhu, and Yan Xu
Inorganic Chemistry Article ASAP
DOI: 10.1021/ic302134m
Publication Date (Web): November 26, 2012
Copyright © 2012 American Chemical Society

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