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A b i n i t i o SCF and CI calculations of the dipole moment function of ozoneAb initio self-consistent field and configuration interaction (SCF-CI) calculations with a minimal basis set are carried out on a few lower 1T-1T* states of free base porphin and free base chlorin. Excitation energies and oscillator strength of these states are calculated and are compared with observed values. For the two lowest states of porphin and chlorin, the calculated excitation energies and oscillator strength are in good agreement with the observed ones. In particular, a characteristic of chlorin spectra is reproduced by the calculation. Namely, the oscillator strength of the lowest transition is several times larger than that of porphin but the oscillator strength of the second transition is similar to that of porphin. Such differences of the oscillator strength between chlorin and porphin are explained by an interchange of the order of two highest occupied orbitals and that of the two lowest unoccupied orbitals. Those differences are caused by a change of orbital shapes of chlorin due to the addition of two hydrogen atoms to the porphin skeleton.

The structure (I) of a new alkaloid, stemofoline isolated from the stems and leaves of Stemona japonica has been determined by X-ray crystallographic analysis of its hydrobromide monohydrate.