Communications to the Editor 3035 ly difficult to determine the angle with precision. This minimum may therefore "correspond" to the 27 and the 2.27 helices at ^75°, -70°for polyglycine.19 Maigret, et al.,20 found the conformation -80°, =: -40°t o be the most stable conformation in their calculation on '-acetyl-N'-methylalanylamide. The local minimum =* -60°, ^60°of approximately 4 kcal/mol of residue obtained for the tetrapeptide of glycine17 has disappeared in the present calculation and this , pair is now on a 6 kcal/mol of residue contour. There is a suggestion, however, of the formation of a new local minimum at about ^-70°, ^50°, of slightly less than 4 kcal/mol of residue.The local minimum near the fully extended chain conformation of about 5 kcal/mol of residue has shifted from =s! -180°, ce. -180°for the tetrapeptide of glycine17 to ^-180°, ^-165°in the present case. Hence, there is a faint suggestion of pleating21 on substituting the bulkier CH3 group for H in the side chains.The partial charges which are sensibly independent of the rotation angles and are substantially the same as for the tetrapeptide of glycine17 and are given in Table II for some selected conformations.

Few-molecule vibrational strong coupling in a microcavity using cavity optomechanics and its application as cavity-mediated thermodynamic coupling of chemical reactions.

No abstract