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：1990
卷号：87
期号：19
页码：7570-7573
DOI：10.1073/pnas.87.19.7570
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Low-dose, high-resolution electron microscopy combined with conventional direct-phasing methods based on the estimates of triplet-structure invariants are used to determine phase values for all observed electron-diffraction-structure factor magnitudes from epitaxially oriented multilamellar paracrystals of the phosphospholipid 1,2-dihexadecyl-sn-glycerophosphoethanolamine. The reverse Fourier transform of these phase-structure factors is a one-dimensional electrostatic potential map that strongly resembles the electron-density maps calculated from similar x-ray-diffraction data. Determination of the phase values for the electron-diffraction data with structure invariants alone is nearly as successful as the combined use of two separate methods, assigning values to 13 of the 16 reflections--i.e., the electrostatic potential map closely resembles the one calculated with all data.
