Effects of Isomerization on the Measured Thermochemical Properties of Deprotonated Glycine/Protic‐Solvent Clusters

The thermochemical properties associated with the formation of an isomeric distribution of ROH???NH₂CH₂COO^? clusters (R=H, CH₃, C₂H₅) are measured by using high‐pressure mass spectrometry. A comparison of the measured properties with calculated values provides new insights into the thermochemical effects arising from the isomeric nature of this clustering system. When the distribution of isomers is correctly accounted for, the measured values of ΔH°, ΔS°, and ΔG°₂₉₈ consistently agree, to a very high degree of accuracy, with those predicted by MP2(full)/6‐311++G(d,p)//B3LYP/6‐311++G(d,p) calculations.