Quantum simulation of phenol-water clusters

We investigate the vibrational ground-state structure and energetics of phe nol-(H2O)(n) (n = 2-5) hydrogen-bonded clusters using the rigid-body diffus ion quantum Monte Carlo method. We find that the complexes of small size (n < 5) are similar to related pure-water clusters(H2O)(n+1) and that quantum zero-point effects influence their structure. We calculate the vibrational ground-state structure of phenol-(H2O)(5) and show that pi-hydrogen bondin g between water and the aromatic cycle may be relevant in explaining unusua l features of the experimental jet-cooled infrared spectrum.