HIGH RESOLUTION FLUORESCENCE EXCITATION AND FLUORESCENCE VIBRONIC SPECTRA OF $H_{2}Pc$, MgPc, CIAIPc and ZnPc IN SHPOLS'KII MATRICES AT $4.2 K^{*}$

$^{*}$ Date collected during Huang's research associateship at Simon Fraser University, and analyzed at Xerox Research Centre of Canada.Author Institution:We show for the first tune the high resolution fluorescence-excitation and fluorescence vibronic spectra of $H_{2}Pc$, MgPc, CIAIPc and ZnPc in normal alkane mixed with some $\alpha$-Chloronaphthalene or tetrahydrofuran at 4.2 K. Vibrational analysis basing on the assumption that the first excited, double degenerate singlet was split by the Jahn Teller effect stabilized by the crystal field was done on the long and structurally rich fluorescence excitation and fluorescence vibronic progressions of each molecule. This analysis reveals many more vibronic bands than those reported by Koromaev and Personov(KP)$^{1}$. and by $Gorokhovskii^{2}$. Vibronic bands with vibrational energies larger than $1600 cm^{ -1}$ are observed for the first time in $H_{2}Pc$, and are assigned mostly to the overtones or combinations. The excitation spectrum of each molecule studied also shows the diffuse structure which we attributed to the $n\rightarrow\pi^{*}$ $transition.^{3}$ Of particular interest is the finding from the vibrational analysts that in MgPc, but not in $H_{2}Pc$ and CIAIPc, the two fluorescence-excitation progressions originate from the doublet $(14940 ~\mbox{cm}^{-1}, 14898 ~\mbox{cm}^{-1})$ whereas the fluorescence progressions from $(14898~\mbox{cm}^{-1},14898~\mbox{cm}^{-1})$. In ZnPc, the corresponding origins are found to be $(14945~\mbox{cm}^{-1}$, $14914 ~\mbox{cm}^{-1})$ and $(14914~\mbox{cm}^{-1}14885~\mbox{cm}^{-1})$. This confirms qualitatively Kp’s important observation, done in the origin regions of the MgPc and ZnPc vibronic transitions for the type of scattering center they prepared