The cooperative spin transition in [FexZn1 − x(ptz)6](BF4)2: II. Structural properties and calculation of the elastic interaction

Cooperative phenomena and light-induced bistability in iron(II) spin-crossover compounds

“…(1) , respectively. Even though these values were obtained neglecting the temperature dependence of DH HL x 0 and DS HL x 0 , they are reasonably close to values obtained using more sophisticated procedures [16,17]. The ratio Z/Y: 2, predicted for the isostructural zinc lattice, is nicely fulfilled.…”

“…Fig. 1 [16,17]. The spin transition for the diluted compound is gradual with T 1/2 =95 K, the one for the neat compound is steep and shows a thermal hysteresis.…”

“…, and Z=Y =0 for the diluted system, and Z= 310 and 380 cm − 1 , and Y=165 and 144 cm − 1 for the neat compound in the high-temperature and the low-temperature phase, respectively (adapted from Refs. [16,17]). …”

Correlations of the distribution of spin states in spin crossover compounds

“…In fact, the contribution of the elastic interactions has been studied in detail both theoretically [18,19] and experimentally by measuring elastic constants by Brillouin spectroscopy [20] and temperature dependent X-ray diffraction [21]. It turns out that the interaction constants obtained from transition curves of the metal dilution series in [Fe x Zn 1 − x (propyltetrazole) 6 ](BF 4 ) 2 essentially are explained by the elasticity theory (about 80%), where the molecules are treated as point defects and the lattice as a homogeneous medium [22,23]. This approximation, however, does not describe well the interactions at short distances comparable with the size of the molecules.…”

Cooperative formation of high-spin species in a photoexcited spin-crossover complex

“…33 They have found that the chemical substitution significantly modifies the LS-HS transudation temperature, and have ascribed the chemical impurity effect to the strain effect. 34 For example, T c of ͓Fe 1−x Zn x ͑ptz͒ 6 ͔͑BF 4 ͒ 2 decreases in proportion to the concentration x of the Zn 2+ impurity as T c Ϸ 130− 30x.…”