Hyperfine Interactions and Metal Atom Dynamic Effects of Pentafluorophenyl Substituents on Ferrocene Complexes

Iron and tin atom dynamics and hyperfine interactions of two structurally related half-sandwich complexes bearing a distannyl moiety

“…The temperature dependence of the logarithm of the recoil-free fraction, f, which, for an optically thin absorber, is given by the temperature dependence of the logarithm of the area under the resonance curve is well fitted by a linear regression, with r ¼ 0.997 for 7 data points. This linear regression in turn permits the calculation [3] of a "Mössbauer lattice temperature", Q M , of 106 AE 8 K as probed by the iron atom, comparable to that reported for similar iron-organometallics [4]. In addition, as has been reported in the recent literature [4], this linear dependence further permits the calculation of the ₣ parameter, where ₣ ¼ k 2 <x ave 2 >, from which the mean-square-amplitude-of-vibration (<x ave 2 >, msav) of the metal atom can be calculated at various temperatures and compared the corresponding value extracted from the single-crystal U i,j data extracted from the relevant X-ray data.…”

“…This linear regression in turn permits the calculation [3] of a "Mössbauer lattice temperature", Q M , of 106 AE 8 K as probed by the iron atom, comparable to that reported for similar iron-organometallics [4]. In addition, as has been reported in the recent literature [4], this linear dependence further permits the calculation of the ₣ parameter, where ₣ ¼ k 2 <x ave 2 >, from which the mean-square-amplitude-of-vibration (<x ave 2 >, msav) of the metal atom can be calculated at various temperatures and compared the corresponding value extracted from the single-crystal U i,j data extracted from the relevant X-ray data. In this context it is to be emphasized that it is assumed that f / 1 as T / 0; that is, that the zero point motion is assumed to be negligibly small in these cases.…”

One electron oxidation of triferrocenylmethanol: synthesis, metal atom dynamics, electron delocalization, and the crystal structure of [Fc3COH]+ PF6−

“…14, 17 Two independently synthesized samples (a and b) were examined in this study. In order to ensure that no sample loss was incurred during the lengthy data acquisition times, the transmission counting rate was monitored before and after each temperature-dependent data point.…”

Metal atom dynamics in a charge transfer complex

“…The corresponding values are M eff (1) ¼ 108 AE 8 Da and M eff (2) ¼ 71 AE 7 Da. As noted earlier [5] the difference between these M eff values and the "bare" iron value of 55.85 Da, reflects the covalency in the metal atom-ligand bonding.…”

“…As has been noted previously [3,5], the -ln [A(T)/A(90)] data are most succinctly represented by ₣ ¼ (k 2 <x ave 2 >), where k is the wave vector of the ME gamma ray (k ¼ 7.304 Â 10 8 cm À1 ) and x ave 2 is the mean square amplitude of the metal atom vibration. Making use of the assumption that the high temperature ME data above T PT can be normalized postulating that f / 1 as T / 0, permits not only the comparison of the vibrational amplitude extracted from the ME data shown in Fig.…”