New paramagnets based on nanocarbon and cobalt(II)porphyrin: Magnetocaloric effect and specific heat capacity

Авторы публикации: 
Tatyana N. Lomova⁎, Victor V. Korolev, Nataliya G. Bichan, Ekaterina N. Ovchenkova, Anna G. Ramazanova, Olga V. Balmasova, Matvey S. Gruzdev
Synthetic Metals
Год публикации: 
Volume 253, July 2019, Pages 116-121

This article represents the first unique data about a new paramagnets based on a carbon nanoform composited
with cobalt(II) porphyrin with both a photoinduced electron transfer and a room-temperature magnetocaloric
effect. Magnetocaloric effect values/magnetization thermodynamic parameters and specific heat capacity have
been directly determined for the donor-acceptor triad derived from cobalt(II)5,10,15,20-(tetra-4-tert-butylphenyl)
21H,23H-porphyrin and 1′-N-methyl-2′-(pyridin-4-yl)pyrrolidino[3′,4′:1,2][60]fullerene via axial coordination
and compared with those for C60 and the precursors. The studies were performed by the original
microcalorimetric method developed by us and differential scanning calorimetry. The samples display the positive
magnetocaloric effect that has been determined to be equal, to 0.004 (C60), 0.016 (PyC60), 0.028(porphyrin
complex), and 0.007 K (triad) at 278 K and 1.0 T. The magnetocaloric effect values observed are comparable
with those in metal-based magnetic materials but unlike those, the studied triad demonstrates a
photoinduced electron transfer. The contributions of aromatic electron systems to the magnetization thermodynamic parameters have been analyzed.

Ломова Татьяна Николаевна