Knowledge Bank

Very complete Raman spectra have been obtained of tetramethyllead, trimethylethyllead, dimethyldiethyllead, methyltriethyllead, tetraethyllead, and completely deuterated tetraethyllead, in the liquid state and of crystalline tetramethyllead. In order to prevent photodecomposition, it was necessary to expose all samples, except tetramethyllead, at about $-120\circ C$. Infrared data have been obtained for $Pb(CH3)4,H3CPb(C2H5)3,Pb(C2H5)4$, and $Pb(C2D5)4$. The fundamental vibrational frequencies of $Pb(CH3)4$ have been assigned, in essential agreement with the results of previous investigators. The effect of the crystalline field is discussed. A normal coordinate analysis of the $a1$, e, and $f2$ vibrations of tetramethyllead is underway.