FIGURE 4.

DFT optimized geometry and frequencies for ν_asym and ν_sym normal modes for isolated and interacting E222 at the B3LYP 6-311+G(2p,2d) level. (A) Bond angle and lengths for a geometry optimized model including hydrogen-bonding interactions to water Z223 and S205. Displacement vectors and calculated frequency of ν_asym are shown. (B) Displacement vectors and frequency of ν_sym for interacting E222. (C) Bond angle and lengths for a geometry optimized model excluding hydrogen-bonding interactions but maintaining dihedral angles taken from the x-ray geometry, and vectors and calculated frequency of ν_asym. (D) Displacement vectors and frequency of ν_sym for isolated E222