Physical Chemistry

A Post-HF Approach to the Sunscreen Octyl Methoxycinnamate



Octyl methoxycinnamate (OMC) is a commercial sunscreen with excellent UVB filter properties. However, it is known to undergo a series of photodegradation processes that decrease its effectiveness as UVB filter. In particular, the trans (E) form - which is considered so far the most stable isomer - converts to the cis (Z) form under the effect of light. In this work, by using post-Hartree-Fock approaches (CCSD, CCSD(t) and CCSD+T(CCSD)) on ground state OMC geometries optimized at the MP2 level we show that the cis and trans form of the gas-phase OMC molecule have comparable stability. Our results suggest that the cis form is stabilized by intra-molecular dispersion interactions, leading to a folded, more compact structure than the trans isomer.

Version notes

second version submitted to ChemRxiv


Thumbnail image of Octinoxate_Preprint_Second_Version.pdf

Supplementary material

Thumbnail image of Cis2_mp2_gopt.png
Cis2 mp2 gopt
Thumbnail image of
Optimized Geometries