Cobaltocenium [1,2,5]Thiadiazolo[3,4‐c][1,2,5]thiadiazolidyl: Synthesis, Structure, and Magnetic Properties

Abstract

(5) in 93 % yield. The XRD structure of 5 displays layers of radical anions 1, with S···N contacts of 358.2 and 366.0 pm between neighboring species. The salt was further characterized by ESR spectroscopy in the solid state as well as in solution. The temperature dependence of its magnetic susceptibility (χ) in the range of 2-300 K with a maximum at (9.7 Ϯ 0.5) K indicates antiferromagnetic ordering of the spin system. The magnetic structure of 5 was analyzed in terms of dimeric exchange integrals calculated by a spin-unrestricted broken-

Metal-radical coordination complexes of thiazyl and selenazyl ligands

“…However, species incorporating the 125TDA can be reduced by one electron to resonance stabilized radical anions, and ionic compounds involving 125TDA radical anions can be prepared and isolated as crystalline solids [107][108][109][110]. As observed with thiazyl radical cations (vide supra), ionic complexes of 125TDA radical anions that incorporate a metal-containing counterion may also exhibit structural features consistent with coordination between the thiazyl radical and the metal.…”

Redox properties and radical anions of fluorinated 2,1,3‐benzothia(selena)diazoles and related compounds

“…The DFT approach at the (U)B3LYP/6‐31+G(d)39, 40 level of theory was used for the calculations since it performs well for molecular structures and properties of main‐group compounds including electron affinities and hyperfine coupling constants 20, 41, 42. Previously, the (U)B3LYP method was successfully employed to reproduce the properties of a series of both closed‐ and open‐shell chalcogen–nitrogen cycles and cages including RAs 25–31, 43–50. Quantum chemical calculations on RAs and their neutral precursors were carried out with full geometry optimization using the GAMESS51 and GAUSSIAN‐0352 programs.…”

“…Being interested in stable π ‐heterocyclic RAs as the promising building blocks for magnetically active molecular materials,25–31 we performed the verification of the aforementioned hypothesis. In this study we report on the redox properties and radical anions of fluorinated heteroaromatics 3 and 4 and related derivatives 5 – 11 (Chart ).…”

Synthesis and Properties of the Heterospin (S1=S2=1/2) Radical-Ion Salt Bis(mesitylene)molybdenum(I) [1,2,5]Thiadiazolo[3,4-c][1,2,5]thiadiazolidyl

“…The utility of DFT applications to transition metal derivatives has been comprehensively discussed recently. 30 First of all, properties of the cation 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 are −3.9, 0.08 and 0.06 cm -1 for R Mo…S = 5.22,6.93 and 5.90 Å,respectively (Figure S8,Supporting Information 6,7 Elemental analysis data indicated decomposition with partial loss of Mes ligands. According to solid-state EPR and magnetometry, the final decomposition product is diamagnetic, whereas partially decomposed samples revealed interesting paramagnetic properties different from those of initial salt 2 ( Figure S9, Supporting Information) worthy of special study.…”

“…allowing the synthesis of both homo-and heterospin RA salts. 6,7 The resultant salts have complex magnetic structures dominated by antiferromagnetic (AF) exchange interactions associated within the McConnell I model 8 with contacts of like spin density of neighboring paramagnetic species in the solid state. At the same time, the presence of weak ferromagnetic (FM) interactions, most likely caused by contacts of unlike spin density in the heterospin salts, was also recognized.…”