FE-57 MOSSBAUER-SPECTRA OF FENI(CN)(4) LAYERED HOST ANILINE CLATHRATES

We measured the Fe-57 Mossbauer spectra of three types of aniline clat hrate materials with a two-dimensional layered host consisting of iron (II)tetracyanonickelate(II). The formation of the three aniline clathr ate materials depends on the pH of the mother aqueous solution contain ing equimolar amounts of (NH4)(2)Fe(SO4)(2) . 6H(2)O and K-2[Ni(CN)(4) ]. H2O. The spectra for the three clathrate materials indicate that al l the iron atoms are in iron(II) high spin states. In the spectrum of material I obtained from the relatively high pH (8-10) solution, there exists one kind of doublet with quadrupole splitting(QS) of 1.44mm/s. Material I is previously known as Fe(NH3)(2)Ni(CN)(4) . 2C(6)H(5)NH(2 ). In material III, obtained from the relatively low pH (5-6) solution , the quadrupole splitting of 2.42mm/s is larger than that of I. The M ossbauer data i.r. and elemental analysis for III suggest that the pro bable composition is Fe(H2O)(2)Ni(CN)(4) .[mH(2)O . nC(6)H(5)NH(2)]. M aterial II obtained from the middle range of pH (6-8), has at least tw o kinds of iron(II) sites, I type and III type, respectively.