TY  - JOUR
AB  - We study the influence of Alizarin Red S deprotonation on molecular self-assembly at the solid-liquid interface of the natural cleavage plane of calcite immersed in aqueous solution. To elucidate the adsorption details, we perform pH dependent high-resolution atomic force microscopy measurements. When Alizarin Red S is deposited onto calcite(10.4) in a liquid environment at an acidic pH of 5, weakly bound, ordered islands with a (3 x 3) superstructure are observed. A sharp structural transition is revealed when increasing the pH above 8. Above this pH, stable needle-like structures oriented along the [01.0] direction form on the surface. Comparing these results with potentiometric titration data allows for unambiguously assigning the two molecular structures to the single and two-fold deprotonated moieties of Alizarin Red S. Our work, thus, illustrates the decisive impact of the protonation state on molecular self-assembly.
DA  - 2013
DO  - 10.1039/c3sm50262g
LA  - eng
IS  - 29
M2  - 7145
PY  - 2013
SN  - 1744-683X
SP  - 7145-7149
T2  - Soft Matter
TI  - How deprotonation changes molecular self-assembly - an AFM study in liquid environment
UR  - https://nbn-resolving.org/urn:nbn:de:0070-pub-29138087
Y2  - 2024-11-22T04:54:35
ER  -