Mouml;ssbauer spectra of the polycrystalline form of the square planar compound agr;,bgr;,ggr;,dgr;hyphen;tetraphenylporphinatondash;iron (II) have been observed at a variety of temperatures. Analysis of the resulting spectra yield a positive electric field gradient interaction with quadrupole splitting Dgr;E=1.51 mm/s (4.2 K) and 1.52 mm/s (300 K). At low temperature, an external magnetic field induces a negligible internal field along the symmetry axis of the molecule. In the transverse direction, it gives rise to a positive internal field with little temperature dependence up to 30 K. The data can be interpreted in terms of a crystal field model involving a lowhyphen;lying3A2gstate which is split by spinndash;orbit coupling into a ground singlet and a doublet lying 80 cmminus;1above it.
展开▼
