Interstellar Porphyrins: Implications
Session 26 -- Interstellar Medium and Radiative Shocks
Oral presentation, Monday, 9, 1995, 10:00am - 11:30am

## [26.03] Interstellar Porphyrins: Implications

Fred M. Johnson (Cal. State U. Fullerton)

Optical spectroscopic evidence (1,2),( in excess of 160 lab and DIB coincidences to $\pm$1 \AA )is given for the presence of tetrabenzoporphyrins MgTBP and H$_2$TBP in interstellar grains. Based on this evidence, a possible relationship between these molecules and a group of small organic molecules observed in interstellar space will be explored. MgTBP ion fragments, in the mass range 29-117, were produced by 70 ev electrons and analyzed by means of a high resolution mass spectrometer. Ten of the MgTBP fragments, including MgNC, can be identified with the above group of observed interstellar molecules. Implications of these experiments include the possibility that this group of interstellar molecules results from grain disintegrations. The mass spectral data provides a list of additional interstellar molecular candidates to be searched for in the microwave region. Scenarios for efficient organic molecular synthesis will be presented.

(1) Johnson, F.M., 1994, Proc. Symp. Diffuse Interstellar Bands, p.47 NASA Conf. Publ. 10144, Editor:A.G.G.M.Tielens

(2) Johnson, F.M., 1994, Invited paper of above Symposium,Kluwer Pub., in press