pH-independent decomposition reactions of L-ascorbic acid in aqueous metal solutions .1. Formation and structures of Co-II and Gd-III oxalates


UNALEROGLU C. , ZUMREOGLU KARAN B., ZENCIR Y. , Hokelek T.

POLYHEDRON, cilt.16, ss.2155-2161, 1997 (SCI İndekslerine Giren Dergi) identifier

  • Cilt numarası: 16 Konu: 13
  • Basım Tarihi: 1997
  • Doi Numarası: 10.1016/s0277-5387(96)00563-3
  • Dergi Adı: POLYHEDRON
  • Sayfa Sayıları: ss.2155-2161

Özet

The reactions of L-ascorbic acid in aqueous Cd-II and Gd-III solutions were investigated at pH values of 2, 6 and 12. IR spectral studies revealed that the initially formed metal-ascorbates slowly decompose to the solid oxalate complexes in a pH-independent manner. The compositions of the cobalt oxalates were defined as CoC2O4 . 2H(2)O and those of Gd-III showed variations due to the stereochemical changes in the precursor ascorbate complexes related to pH. X-ray crystal analyses were performed and the structure of Gd-2(C2O4)(3) . 6H(2)O is reported for the first time. (C) 1997 Elsevier Science Ltd.