Spontaneous Magnetization in a Sulfur–Nitrogen Radical at 36 K
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Dougherty D. A., 1993, Research Frontiers in Magnetochemistry
Cordes A. W., 1995, The Chemistry of Inorganic Ring Systems
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1β: C8F4N3S2 Mr= 278.23 orhorhombic Fdd2 a= 15.105(3) b= 10.828(2) c= 11.933(3) Å V= 1951.7(8) Å3 Z= 8 (molecule lies on a twofold rotation axis) ρcalcd= 1.894 gcm−3 μ = 0.582 mm−1(Mokαradiation λ = 0.71073 Å) F(000) = 1096 T= 160 K. Of 1403 reflections measured on a Stoe‐Siemens diffractometer and corrected semiempirically for absorption (transmission 0.650–0.789) 865 were unique data (2θ <50° Rint= 0.0248). The structure was solved by direct methods and refined by full‐matrix methods onF2values for all reflections [14] with anisotropic displacement parameters and statistical weights to givewR2 = {Σ[w(F–F)2]/Σ[w(F)2]}½= 0.0784; conventionalR= 0.0315 forFvalues of all reflections goodness of fitS= 1.057 onF2for all reflections and 80 refined parameters; largest residual electron density 0.22/–0.16 e Å−3; the refined enantiopole parameter of −0.11(10) indicates the correct absolute structure [15]. Crystallographic data (excluding structure factors) for the structure reported in this paper have been deposited with the Cambridge Crystallographic Data Centre as supplementary publication no. CCDC‐179‐93. Copies of the data can be obtained free of charge on application to The Director CCDC 12 Union Road Cambridge CB21 1EZ UK (fax: Int. code +(1223)336‐033; e‐mail: [email protected]. ac.uk).
Static magnetization measurements were performed on an Oxford Instruments Maglab Faraday Balance (University of Durham): A typical sample of material (50–150mg) was cooled to 4.2 K in zero magnetic field and data were recorded at increasing temperature in applied fields of 0.1 0.5 1.0 3.0 and 5.0 T. Further measurements were made on Quantum Design SQUID magnetometers (University of Zaragoza and University of Edinburgh) between 1.8 and 300 K. Alternating current susceptibility measurements were made on a SQUID magnetometer equiped with an a.c. susceptibility attachment (Zaragoza). In another set of experiments isothermal magnetization curves were measured as a function of the magnetic field.
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Sheldrick G. M., 1993, SHELXL‐93, program for crystal structure refinement