## Abstract The crystal structures and magnetic properties of the nitronyl nitroxide radicals 4,5‐dihydro‐4,4,5,5‐tetramethyl‐3‐oxido(1__H__‐imidazol‐1‐yloxyl) (**1**), 4,5‐dihydro‐2,4,4,5,5‐pentamethyl‐3‐oxido(1__H__‐imidazol‐1‐yloxyl) (**2**), 2‐(4‐chlorophenyl)‐4,5‐dihydro‐4,4,5,5‐tetramethyl‐3‐
Magnetic and structural properties of monoradicals and diradicals based on thienyl-substituted nitronyl nitroxide
✍ Scribed by Tadashi Sugano; Stephen J. Blundell; William Hayes; Peter Day; Hatsumi Mori
- Publisher
- Elsevier Science
- Year
- 2010
- Tongue
- English
- Weight
- 498 KB
- Volume
- 405
- Category
- Article
- ISSN
- 0921-4526
No coin nor oath required. For personal study only.
✦ Synopsis
Magnetic properties of monoradicals and diradicals based on thienyl-substituted nitronyl nitroxide (NN) were investigated by measuring temperature and magnetic-field dependences of magnetization. The magnetic behavior of the monoradical 3-benzo[b]thienyl NN (3-BTHNN) is interpreted in terms of the quasi-2D ferromagnetic Heisenberg model with the coupling constant J/k = +0.16 K and J 0 /k= + 0.02 K, while the alternating antiferromagnetic (AFM) intermolecular interactions are observed in the monoradicals, 2-and 3-thienyl NN (2-and 3-THNN). In contrast, the magnetic behavior of the diradicals, 2,3-and 2,5-bis(NN)thiophene (2,3-and 2,5-THBNN), is explained by quite strong AFM intramolecular interactions between the two spin centers, each located on the two NN moieties. We discuss here the origin of the magnetic interactions observed in these radicals by considering their molecular and crystal structures determined by the X-ray diffraction techniques.
📜 SIMILAR VOLUMES
## Abstract Crystallization of ferrocene and ruthenocene substituted in the 1‐ and 1′‐positions by two nitronyl nitroxide radicals gave the new crystal phases β‐**1** (besides the known phase α‐**1**), α‐**2**, and β‐**2** whose structures were determined by X‐ray analysis. In β‐**1** the radical m