Field-Induced Slow Magnetic Relaxation of a Six-Coordinate Mononuclear Manganese(II) and Cobalt(II) Oxamate Complexes

Tamyris T da Cunha; Vitor M M Barbosa; Willian X C Oliveira; Emerson F Pedroso; Diana M A García; Wallace C Nunes; Cynthia L M Pereira

doi:10.1021/acs.inorgchem.0c01628

Field-Induced Slow Magnetic Relaxation of a Six-Coordinate Mononuclear Manganese(II) and Cobalt(II) Oxamate Complexes

Inorg Chem. 2020 Sep 21;59(18):12983-12987. doi: 10.1021/acs.inorgchem.0c01628. Epub 2020 Sep 8.

Authors

Tamyris T da Cunha^{1

2}, Vitor M M Barbosa², Willian X C Oliveira², Emerson F Pedroso³, Diana M A García⁴, Wallace C Nunes⁴, Cynthia L M Pereira²

Affiliations

¹ Instituto Federal de Educação, Ciência e Tecnologia de Minas Gerais, Campus Avançado Itabirito, R. José Benedito, 139 Santa Efigênia, Itabirito, Minas Gerais 35450-000, Brazil.
² Departamento de Quı́mica, ICEx, Universidade Federal de Minas Gerais. Avenida Antônio Carlos 6627, Pampulha, Belo Horizonte, Minas Gerais 31270-901 Brazil.
³ Centro Federal de Educação Tecnológica de Minas Gerais, Avenida Amazonas 5523, Belo Horizonte, Minas Gerais 30421-169, Brazil.
⁴ Instituto de Fı́sica, Universidade Federal Fluminense, Avenida Gal. Milton Tavares de Souza, s/n Campus da Praia Vermelha, Niterói, Rio de Janeiro 24210-346, Brazil.

PMID: 32897061
DOI: 10.1021/acs.inorgchem.0c01628

Abstract

Two air-stable, isostructural, mononuclear six-coordinate manganese(II) and cobalt(II) oxamate complexes, [M(4-HOpa)₂(H₂O)₂] [4-HOpa = N-4-hydroxyphenyloxamate; M= Mn²⁺ (1) or Co²⁺ (2)], exhibit field-induced slow magnetic relaxation. A bottleneck process is observed throughout the temperature range of 2-20 K for 1, while for 2, it dominates only at low temperatures (2-4 K). Additionally, the Raman process [n = 6.9(2)] is responsible for an increase in the relaxation time at higher temperatures to 2.