期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1980
卷号:77
期号:4
页码:1745-1748
DOI:10.1073/pnas.77.4.1745
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Self-assembled chlorophyll a and pheophytin a systems in thin solid films have been studied by 252Cf plasma desorption mass spectrometry (PDMS). The 252Cf-PDMS spectra of these films show monomer cation and anion molecular ions, ions of molecular aggregates, and positive and negative ion fragmentation patterns arising from the loss of various aliphatic side chains from the chlorin ring. Chlorophyll a films cast from dry carbon tetrachloride solution, in which chlorophyll a is known to occur as the dimer, produced an abundant dimer ion. The highest degree of chlorophyll a self-assembly was observed in chlorophyll a films cast from n-octane solutions. Oligomer ions extending upwards in size to the heptamer were detected in this system.