TY - JOUR

T1 - Electrochemical studies of iron(II) complexeswith 4-amino-1,2,4-triazole possessing spin crossover

AU - Kokovkin, Vasily V.

AU - Kal'nyi, Danila B.

AU - Korotaev, Evgenii V.

AU - Shakirova, Olga G.

AU - Lavrenova, Ludmila G.

N1 - Funding Information: The work was partly supported by the Russian Science Foundation (grant No 20‐63‐46026). The authors are grateful for the financial support. Publisher Copyright: © 2021 Wiley-VCH GmbH Copyright: Copyright 2021 Elsevier B.V., All rights reserved.

PY - 2021/8/26

Y1 - 2021/8/26

N2 - The electrochemical properties of a number of coordination compounds of iron(II) with 4-amino-1,2,4-triazole (NH2trz), which have a sharp thermally induced spin crossover with hysteresis on the temperature curves of the effective magnetic moment dependence, were studied using method cyclic voltammetry (CV) at 298 K. The complexes were mixed with carbon powder and silicon oil and included in the paste electrode. The measurements were made in solutions of 0.10 M KNO3. It was found that the area 0.5–0.6 V and 0.3–0.4 V contains the anode and cathode current peaks of freshly prepared paste electrodes. In all cases, the redox process in the paste is quasi-reversible. At the same molar concentration of complexes in the paste (0.1 mol kg−1), a number of current peaks depends on the nature of the anion. The peak current value correlates with the calculated fraction of the high spin form in the solid phase of the complex and the temperature of the direct spin crossover (when heated, Tc↑). The magnetic properties of Fe(NH2trz)3(NO3)2 complex, its mixture with carbon powder and the paste were measured by Faraday method in a temperature range 80–370 K. The effective magnetic moment was depended on changes in variations in the environment of the molecules of the complex in the studied samples.

AB - The electrochemical properties of a number of coordination compounds of iron(II) with 4-amino-1,2,4-triazole (NH2trz), which have a sharp thermally induced spin crossover with hysteresis on the temperature curves of the effective magnetic moment dependence, were studied using method cyclic voltammetry (CV) at 298 K. The complexes were mixed with carbon powder and silicon oil and included in the paste electrode. The measurements were made in solutions of 0.10 M KNO3. It was found that the area 0.5–0.6 V and 0.3–0.4 V contains the anode and cathode current peaks of freshly prepared paste electrodes. In all cases, the redox process in the paste is quasi-reversible. At the same molar concentration of complexes in the paste (0.1 mol kg−1), a number of current peaks depends on the nature of the anion. The peak current value correlates with the calculated fraction of the high spin form in the solid phase of the complex and the temperature of the direct spin crossover (when heated, Tc↑). The magnetic properties of Fe(NH2trz)3(NO3)2 complex, its mixture with carbon powder and the paste were measured by Faraday method in a temperature range 80–370 K. The effective magnetic moment was depended on changes in variations in the environment of the molecules of the complex in the studied samples.

KW - cyclic voltammetry

KW - iron complex

KW - paste electrode

KW - platinum electrode

KW - spin crossover

UR - http://www.scopus.com/inward/record.url?scp=85110331644&partnerID=8YFLogxK

U2 - 10.1002/zaac.202100102

DO - 10.1002/zaac.202100102

M3 - Article

AN - SCOPUS:85110331644

VL - 647

SP - 1620

EP - 1624

JO - Zeitschrift fur Anorganische und Allgemeine Chemie

JF - Zeitschrift fur Anorganische und Allgemeine Chemie

SN - 0044-2313

IS - 16-17

ER -