TITLE:
Synthesis, Characterization and Thermal Analysis of an Organic-Inorganic Hybrid Salt Involving Trans-Diaquabis(oxalato-κ2O1,O2)chromate(III) Complex Anion with Piperidinium as Counter Cation
AUTHORS:
Pierre R. Ndong, Martin Signé, Patrice T. Kenfack, Yves A. Mbiangué, Gouet Bebga, Emmanuel Wenger
KEYWORDS:
Hybrid Salt, Diaquabis(oxalato)chromate(III) Complex, Crystal Structure, Layered Structure, Spectroscopy, Thermal Analysis
JOURNAL NAME:
Crystal Structure Theory and Applications,
Vol.9 No.2,
May
28,
2020
ABSTRACT: A new organic-inorganic hybrid salt pipéridinium trans-diaquabis(oxalato)- chromate(III)
tetrahydrate, (C5H10NH2)[Cr(C2O4)2(H2O)2]·4H2O
(1), has been synthesized in water and characterized by FTIR and UV-Vis
spectroscopies, elemental and thermal analyses and by single-crystal X-ray
diffraction. 1 crystallizes in the
orthorhombic non-centrosymmetric space group Cmc21 with the unit cell parameters a =
7.4329(3), b = 9.9356(5), c = 23.6756(11) Å, α = β = γ = 90°, V = 1748.45(14) Å3 and Z = 4. The structure of 1 consists of [Cr(C2O4)2(H2O)2]- mononuclear anions, piperidinium cations and uncoordinated water molecules. The
CrIII ion in the complex [Cr(C2O4)2(H2O)2]- is coordinated in a slightly distorted octahedral environment by four O atoms
from two chelating oxalate dianions in the equatorial plane, and two O atoms
from trans-coordinated water
molecules occupying the apical positions. In the crystal, N-H···O and O-H···O hydrogen bond
interactions connect the components into a 3-D framework. The IR spectrum of 1 is consistent with the presence of the various molecular building
constituents, namely oxalato and aqua ligands, piperidinium cations and solvent
water molecules. The UV-Vis spectrum shows two absorption bands around 564 and
416 nm which are compatible with an anionic chromium(III) complex in an
octahedral environment. Thermal analysis shows a three-step decomposition of 1,
leading to formation of a metal oxide residue.