Университети кимё – технология факультети

Adabiyotlar 
1.
E. Wang, K.Chow, V.Kwan, T.Chin, C.Wong, A.Bocarsly, Fast and 
long term optical sensors for pH based on sol-gels, 
Anal. Chim. Acta.
495 (2003), 
45-50. 
2.
Nasimov A, Buronov A, Isakulova M, Haydarov G , Tashpulatov Kh, 
Optical sensor preparation using the sol-gel technology for dissolved ammonia 
detection, 
Journal of Critical Reviews
, Vol 7, Issue 6, 2020, 104-106 pp 
TEMPLATE SYNTHESIS, STRUCTURE, ELECTROCHEMICAL AND 
MAGNETIC PROPERTIES OF MANGANESE(IV) CLATHROCHELATE 
a
Kalimbetova Rayxan Y., 
b
Husak Alina O., 
b
Ph.D. Iskenderov Turganbay S., 
b
D.Sci. Fritsky Igor O.
 
a
Karakalpak State University 
b
Taras Shevchenko National University of Kyiv 
Clathrochelates represent a specific class of macrobicyclic coordination 
compounds containing metal ion in a three-dimensional cavity. Using template 

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synthetic procedure we succeeded to isolate a unique Mn(IV) clathrochelate 
(Ph
4
As)
2
[Mn(C
12
N
12
O
6
H
12
)]∙13.5H
2
O (
1
) (Fig. 1). The complex is formed 
spontaneously 
starting 
from 
divalent 
manganese, 
formaldehyde 
and 
oxalodihydrazide in alkaline aqueous media in the presence of atmospheric 
oxygen. X-ray single crystal analysis of the complex revealed the presence of the 
clathrochelate complex dianions [Mn
IV
(
L
-6H)]
2-
containing the encapsulated Mn
4+
ion coordinated by six deprotonated hydrazide nitrogen atoms (Fig. 1). 
Figure 1. Molecular structure of hexahydrazide cage manganese(IV) 
complex. 
The cyclic voltammograms of 
1
in acetonitrile solution reveal two one-
electron quasireversible oxidation processes at 
E
1/2 
= 0.050 V with 

E
p
= 80 mV 
and at 
E
1/2 
= 0.540 V vs. Fc/Fc
+
with 

E
p
= 84 mV which can be assigned to the 
Mn
5+/4+
and Mn
6+/5+
redox couples, respectively. At higher potentials, (1.1 V), the 
irreversible redox feature is also observed. Scanning towards the negative 
potentials (down to -1.5 V vs. Fc/Fc
+
) did not reveal the reduction events. In 
aqueous solution, two quasireversible redox processes are registered as well, 
however, the one observed in the negative potential range (at 
E
1/2
= -0.17 V vs. 
NHE with 

E
p
= 86 mV) can be evidently assigned to the one-electron reduction to 
Mn
3+
(Fig. 2). At higher potentials, another redox wave is observed (at 
E
1/2
= 1.05 
V vs. NHE with 

E
p
= 90 mV) which probably corresponds to the one-electron 
oxidation Mn
5+/4
. The reduction and oxidation processes proved to be 
quasireversible for at least 20 cycles. The peak separations 
ΔE
are within the 
typical range for quasireversible one-electron processes. The observed values of 
the redox potentials suggest efficient stabilization of the tetravalent oxidation state 
associated with strong σ-donor capacity of the deprotonated hydrazide groups 
The value of the effective magnetic moment, 

eff
, at 300 K of 4.01 

B
(Fig. 
3) is close to the spin-only value for three unpaired electrons (3.87 

B
). The 

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magnetic moment is constant in the range of 5–300 K, which indicates a high spin 
ground state of manganese(IV) (S=1.5). Below 5 K, 

eff
slightly drops till 3.94 

B
at 1.85 K due to magnetization saturation at 0.5 T. of manganese(IV) (S=1.5). 
Below 5 K, 

eff
slightly drops till 3.94 

B
at 1.85 K due to magnetization saturation 
at 0.5 T.
Figure 2. The cyclic voltammogram of 
1
in 
aqueous solution (1 mM) with addition of 
NaClO
4
(1 M) as supporting electrolyte in the 
range of -0.7 – -0.2 V at a scan rate of 25 mVs
-
1
Figure 3. Temperature dependence of magnetic 
moment for the crystalline sample of