ORIENTAL JOURNAL OF CHEMISTRY
www.orientjchem.org
An International Open Access, Peer Reviewed Research Journal
ISSN: 0970-020 X
CODEN: OJCHEG
2019, Vol. 35, No.(5):
Pg. 1500-1507
This is an Open Access article licensed under a Creative Commons license: Attribution 4.0 International (CC- BY).
Published by Oriental Scientific Publishing Company © 2018
Complex of Tris(phenanthroline)cobalt(II) Trifluoroacetate:
Characterisation and Powder XRD Analysis
ISANA SUPIAH YOSEPHINE LOUISE, SAVETSILLA NABILA
and KRISTIAN HANDOYO SUGIYARTO*
Department of Chemistry Education, Yogyakarta State University, Jl. Colombo No.1.,
Yogyakarta 55281, Indonesia.
*Corresponding author E-mail: sugiyarto@uny.ac.id
http://dx.doi.org/10.13005/ojc/350504
(Received: September 13, 2019; Accepted: October 03, 2019)
ABSTRACT
The powder complex of tris(phenanthroline)cobalt(II) trifluoroacetate (TFA) has been prepared
by interaction of cobalt(II) nitrate, phenanthroline (phen) in aqueous solution with drops of ethanol, and
an excess of saturated aqueous solution of sodium trifluoroacetate, where upon the yellowish powder
was produced. AAS measurment for the metal content, equivalent conductance (1:2), and TGA-DTA
of the powder suggest the corresponding formula of [Co(phen)
3
](TFA)
2
.5H
2
O. The efffective magnetic
moment of 4.9 BM indicates the high-spin nature of this complex which corresponds to three unpaired
electrons in the electronic configuration of Co(II) with significantly higher than the spin only value due
to the orbital contribution. UV-Vis spectrum of the complex reveals the d-d spin-allowed transition
bands as well as the MLCT and intraligand band. The estimating transition energy ratio of 2.04 for
ν
2
/ν
1
, is clearly in the range for octahedral configuration. The infrared results property indicates the main
mode of vibrations for the functional groups of ligand phen and TFA, and thus supports the formula
proposed for this complex. The corresponding powder XRD was then refined using Rietica-Le Bail
method and found to be fit as triclinic crystal system with space group of PI.
Keywords: Rietica, Phen, Trifluoroacetate, Cobalt(II).
INTRODUCTION
Crystal structure of tris-bidentate-cobalt(II)
complexes have been well known, particularly
those with N-donor atoms in six-membered ring
system, bipyridine (bipy)
1,2
and 1,10-phenanthroline
(phen)
3
. Structural studies through single crystal
XRD analyses of tris(phen)cobalt(II) with several
counter anions, the perchlorate (ClO
4
)
4
, squarate
(C
4
O
4
)
5
, tetrathionate (S
4
O
6
)
6
, triiodide (I
3
)
7
and the
trichloroacetate (CCl
3
COO)
8
have been well refined.
The point is that the cell parameters for the cationic
complex in those complexes are different one to
another even though the symmetry and space
group of the crystal may or may not the same class.
Therefore, discussing the cell parameters through
other simple method by powder X-ray diffraction
may be relevant. Quite recently, the cell parameters
of some complexes have been estimated from the
corresponding powder-XRD by applying Le Bail