A design for an octahedrally ligated phthalocyanine complex with high-spin manganese(iii) ( = 2) and Mn(Pc)Cl (Pc = phthalocyanine) is presented. The presence of high-spin state Mn in the fabricated PhP[Mn(Pc)Cl] (PhP = tetraphenylphosphonium) semiconducting molecular crystal is indicated by the Mn-Cl distance, which suggests an electronic configuration of (d , d )(d )(d ). This was confirmed by the Curie constant ( = 5.69 emu K mol), which was found to be significantly larger than that of the isostructural PhP[Mn(Pc)(CN)], where Mn adopts a low-spin state ( = 1). The magnetoresistance (MR) effects of PhP[Mn(Pc)Cl] at 26.5 K under 9 T static magnetic fields perpendicular and parallel to the -axis were determined to be -30% and -20%, respectively, which are significantly larger values than those of PhP[Mn(Pc)(CN)]. Furthermore, the negative MR effect is comparable to that of PhP[Fe(Pc)(CN)] ( = 1/2), which exhibits the largest negative MR effect reported for [M(Mc)L]-based systems (Mc = macrocyclic ligand, L = axial ligand). This suggests that the spin state of the metal ion is the key to tuning the MR effect.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9204555 | PMC |
http://dx.doi.org/10.1039/d2ra00188h | DOI Listing |
Dalton Trans
January 2025
School of Chemistry, UNSW Sydney, NSW 2052, Australia.
In my proposed mechanism of Mo-nitrogenase there are two roles for separate N molecules. One N diffuses into the reaction zone between Fe2 and Fe6 where a strategic gallery of H atoms can capture N to form the Fe-bound HNNH intermediate which is then progressively hydrogenated through intermediates containing HNNH, NH and NH entities and then two NH in sequence. The second N can be parked in an N-pocket about 3.
View Article and Find Full Text PDFPhys Chem Chem Phys
November 2024
College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070, China.
Chevrel-type superatoms refer to the ligated transition metal chalcogenide clusters MEL, where the octahedral M is face-capped with cubic chalcogen E (E = S/Se/Te). Most transition metals can form such superatoms and many organic and inorganic ligands can be substituted in solution reactions, which allows these atomic precision species to be easily functionalized and their properties to be tunable. No test was reported for substituting the chalcogens with pnicogens in this class of materials.
View Article and Find Full Text PDFBiocatalytic C-H oxidation reactions are of important synthetic utility, provide a sustainable route for selective synthesis of important organic molecules, and are an integral part of fundamental cell processes. The multidomain non-heme Fe(ii)/2-oxoglutarate (2OG) dependent oxygenase AspH catalyzes stereoselective (3)-hydroxylation of aspartyl- and asparaginyl-residues. Unusually, compared to other 2OG hydroxylases, crystallography has shown that AspH lacks the carboxylate residue of the characteristic two-His-one-Asp/Glu Fe-binding triad.
View Article and Find Full Text PDFInorg Chem
February 2024
Department of Chemistry and Catalysis Research Center, Chair of Inorganic and Metal-Organic Chemistry, Technical University of Munich, Lichtenbergstr. 4, Munich, Garching 85748, Germany.
Key strategies in cluster synthesis include the use of modulating agents (e.g., coordinating additives).
View Article and Find Full Text PDFIUCrdata
October 2023
E-194 Holmes Hall, Michigan State University, Lyman Briggs College, 919 E. Shaw Lane, East Lansing, MI 48825, USA.
The title compound, {[Ni(CHO)(CHNO)]·HO}, contains octa-hedrally coordinated Ni ions ligated by 1,3-adamantanedi-acetato (ada) ligands and -(pyridin-3-yl)isonicotinamide (3-pina) ligands, to form coordination polymer layers with a triangular (3,6) grid topology based on [Ni(OCO)] dimeric units. The diperiodic layer motifs stack in an pattern mediated by C-H⋯O supra-molecular inter-actions between ada ligands and water mol-ecules of crystallization to form the full triperiodic crystal structure of the title compound.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!