Molecular positional order in a dipalmitoylphosphatidic acid Langmuir-Blodgett monolayer by atomic force microscopy

Langmuir-Blodgett monolayers of dipalmitoylphosphatidic acid were studied b y using atomic force microscopy on the large- and nano-scale. A molecularly resolved image was achieved at high surface pressure. The monolayer shows a dramatic long-range orientational and positional ordering of molecular or ganization of aliphatic tails. The ordered molecular arrangement of aliphat ic tails may result from the strong intermolecular hydrogen bonding interac tions between adjacent phosphate groups in the polar region. (C) 1999 Elsev ier Science B.V. All rights reserved.