Jr. Hamon et al., THE 19-ELECTRON FE(I) STATE IN TENTACLED IRON SANDWICHES - SYNTHESIS,STABILITY, MOSSBAUER-SPECTROSCOPY, ELECTRONIC-STRUCTURE AND CHAIN EFFECT, Inorganica Chimica Acta, 240(1-2), 1995, pp. 105-108
The extremely air-sensitive 19-electron [Fe(I)Cp hexaalkylbenzene)] co
mplexes (alkyl = n-propyl, n-butyl, n-pentyl) have been synthesized; v
ariable-temperature Mossbauer data indicate a drastic decrease of the
quadrupole splitting upon increasing temperature which does not corres
pond to a Boltzmann population of the upper Kramer's doubler due to th
e 'chain effect'. It is proposed that an increasing proportion of the
17-electron Fe(I) state is involved as the chain length increases.