Page 141 - Photoreactive Organic Thin Films

120 ZOUHEIR SEKKAT AND WOLFGANG KNOLL

Ji New UV UV

1.68-'

1.66-

1.64-

1.62-

1.60-

1.58-

1.56-

1.54-

FIG. 4.9 Evolution of the 633-nm indices of refraction of the LBK (P^io. '56 monolayers) structure,
under successive UV (360 nm) and blue (450 nm) light irradiations, indicated by the UV and B column
heads. After reference 30, redrawn by permission of ACS.

FIG. 4.10 Schematic drawing of the hairy-rod pofyglutamate double-layer structure. P indicates the
structure's periodicity.The trans isomer can be represented by a highly anisometric, i.e., rtondegenerate,
transition dipole oriented along the alkyl side chains.