Structure of the acetone liquid/vapor interface

Yeh, YL Zhang, C Held, H Mebel, AM Wei, X Lin, SH Shen, YR

Yl. Yeh et al., Structure of the acetone liquid/vapor interface, J CHEM PHYS, 114(4), 2001, pp. 1837-1843

30

INGLESE

Article

Physical Chemistry/Chemical Physics

JOURNAL OF CHEMICAL PHYSICS

0021-9606 → ACNP

114

4

2001

1837 - 1843

ISI

0021-9606(20010122)114:4<1837:SOTALI>2.0.ZU;2-8

The structure of the liquid/vapor interface of acetone is investigated theo retically by molecular dynamics simulation and experimentally by infrared-v isible sum frequency vibrational spectroscopy. The simulation yields the mo lecular orientational distribution at the liquid surface. In conjunction wi th the ab initio calculation, the sum-frequency vibrational spectra for the interface is then computed, allowing a direct comparison to the measured s pectra. As the calculation agrees well with the experiment, we can conclude that the molecules at the liquid surface are polar ordered, with one of th e methyl, groups pointing away from the bulk and the molecular plane perpen dicular to the surface. This orientation is similar to that of molecules in the layer planes of crystalline acetone. Together with the appreciable sur face tension of acetone, it suggests that the acetone liquid surface has a more ordered structure than the bulk and is more or less crystal-like. (C) 2001 American Institute of Physics.