Magnetic specific heat of isotropic linear chains for S⩽⁵/₂

(Nitronyl Nitroxide)‐Substituted Trioxytriphenylamine Radical Cation Tetrachlorogallate Salt: A 2p‐Electron‐Based Weak Ferromagnet Composed of a Triplet Diradical Cation

“…[10, 14b,c] In the latter, the space group may be altered into a non-centrosymmetric one across the NØel temperature (T N ). A hump in the plot of C mag was observed above T N , suggesting one-dimensional antiferromagnetic spin alignment of the NNTOT + spins with the intrachain exchange interaction of J/k B = À1.9 K ( Figure S2 in the Supporting Information), [15] which is in good agreement with the analysis of c dc (T) (Figure 3 a). [14] Heat Capacity Measurements of NNTOT + ·GaCl 4 À To exclude the possibility that the observed phase transition is caused by a minor component possibly involved as an impurity, heat capacity measurements were carried out using single crystals of NNTOT + ·GaCl 4 À .…”

“…[3b] The salt exhibited a single clear peak at the NØel temperature of T N = 2.65 K, which shifted slightly to a lower temperature under a magnetic field greater than 7 T ( Figure S2 in the Supporting Information), thus indicating an antiferromagnetic phase transition. A hump in the plot of C mag was observed above T N , suggesting one-dimensional antiferromagnetic spin alignment of the NNTOT + spins with the intrachain exchange interaction of J/k B = À1.9 K ( Figure S2 in the Supporting Information), [15] which is in good agreement with the analysis of c dc (T) (Figure 3 a).…”

Synthesis, Crystal Structures, and Magnetostructural Correlations in Two New One-Dimensional Nickel(II) Complexes with Azido as Bridging Ligand. Effect of Temperature

“…There is no exact mathematical expression for χ M vs T of infinite Heisenberg chains. Nevertheless, there are numerical calculations that approximately characterize the Heisenberg behavior for 1-D systems. , In the case of isotropic 1-D S = 1 systems the temperature dependence of the susceptibility extrapolated from calculations performed on ring systems of increasing length has been given by Weng where α = | J |/ kT .…”

Specific heat and high-temperature series of lattice models: Interpolation scheme and examples on quantum spin systems in one and two dimensions

“…We look for an approximation of s(e) which satisfies Eqs. ( 9), ( 10), (11) and (13). A two-point Padé interpolation is not directly possible since s(e) is singular in e = e 0 .…”

“…Quantitative extrapolations to N = ∞ of finite-size c v,N (T ) data have been done in spin chains but are not really efficient at low temperatures. It has been applied to spin chains 8,10,11,12 and the triangular antiferromagnet. 13 Power-law behaviors at low temperature cannot be observed due to the important discretization of the low energy spectrum in a small system.…”