Magnetic anisotropy and structural flexibility in the field-induced single ion magnets [Co{(OPPh2)(EPPh2)N}2], E = S, Se, explored by experimental and computational methods. Issue 7 (24th January 2023)

• Record Type: Journal Article
• Authors: Ferentinos, Eleftherios; Tzeli, Demeter; Sottini, Silvia; Groenen, Edgar J. J.; Ozerov, Mykhaylo; Poneti, Giordano; Kaniewska-Laskowska, Kinga; Krzystek, J.; Kyritsis, Panayotis
• Is Part Of: Dalton transactions. Volume 52:Issue 7(2023)
• Page Start: 2036
• Page End: 2050
• Publication Date: 2023-01-24
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d2dt03335f
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : The electronic and magnetic properties of the tetrahedral Co(ii ) complexes [Co{(OPPh2 )(EPPh2 )N}2 ], E = S, Se, are explored by experimental and computational methods, and discussed with respect to their structural features. Abstract : During the last few years, a large number of mononuclear Co(ii ) complexes of various coordination geometries have been explored as potential single ion magnets (SIMs). In the work presented herein, the Co(ii ) S = 3/2 tetrahedral [Co{(OPPh2 )(EPPh2 )N}2 ], E = S, Se, complexes (abbreviated as CoO2 E2 ), bearing chalcogenated mixed donor-atom imidodiphosphinato ligands, were studied by both experimental and computational techniques. Specifically, direct current (DC) magnetometry provided estimations of their zero-field splitting (zfs) axial ( D ) and rhombic ( E ) parameter values, which were more accurately determined by a combination of far-infrared magnetic spectroscopy and high-frequency and -field EPR spectroscopy studies. The latter combination of techniques was also implemented for the S = 3/2 tetrahedral [Co{(EP i Pr2 )2 N}2 ], E = S, Se, complexes, confirming the previously determined magnitude of their zfs parameters. For both pairs of complexes (E = S, Se), it is concluded that the identity of the E donor atom does not significantly affect their zfs parameters. High-resolution multifrequency EPR studies of CoO2 E2 provided evidence of multiple conformations, which are more clearly observed for CoO2 Se2, in agreement with the structural disorder previously established for this complex by X-ray crystallography. The CoO2 E2 complexes were shown to be field-induced SIMs, i.e., they exhibit slow relaxation of magnetization in the presence of an external DC magnetic field. Advanced quantum-chemical calculations on CoO2 E2 provided additional insight into their electronic and structural properties.