Reversible color changes of chiral double salts of d-(+)-camphoric diammonium and transition-metal sulfates via gain and loss of crystalline and coordination water molecules

Autor: Gang Wang, Zhaolian Chu, Kou-Sen Cao, Kun Zhang, Yu-Xin Peng, Wei Huang
Rok vydání: 2011
Předmět:
Zdroj: Inorganica Chimica Acta. 378:224-230
ISSN: 0020-1693
DOI: 10.1016/j.ica.2011.09.015
Popis: Six novel chiral double salts (1–6) composed of d -(+)-camphoric diammonium (LH2) and transition-metal sulfates, formulated as {[M(SO4)2(H2O)4](LH2)}·2H2O [M = Fe(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II)], have been prepared and fully characterized including single-crystal X-ray diffraction, Fourier transform infrared (FT-IR) and vibrational circular dichroism (VCD) spectral investigations. Co(II), Ni(II) and Cu(II) compounds 2–4 exhibit reversible color changes between 20 and 140 °C via gain and loss of two crystalline and four coordination water molecules, which can be proved by their thermogravimetric (TG) and powder X-ray diffraction (PXRD) analyses. To the best of our knowledge, this is the first report on chiral double salts showing chromotropism properties.
Databáze: OpenAIRE