Low-temperature infrared studies of some acid-base reactions

Low-temperature infrared spectroscopy has been used to examine the systems NH 3 + H 2 O, NH 3 + HCl, H 2 O + HCl, NH 3 + HNO 3 , and NH 2 OH + HNO 3 . Hydrogen-bonding in the solid states greatly reduces the reactivities in these systems. Temperatures where reactions initiated in the systems NH 3 (s) + HCl(g), HNO 3 (s) + NH 3 (g), H 2 O(s) + HCl(g), and NH 2 OH(s) + HNO 3 (s) were, respectively, −145, −130, −127, and −125 °C. Infrared spectra of 2NH 3 *H 2 O, NH 3 *H 2 O, NH 4 Cl*3NH 3 , NH 4 NO 3 *3NH 3 , NH 4 NO 3 *2HNO 3 , NH 2 OH 2 + NO 3 − , NH 3 OH + NO 3 − , H 3 O + Cl − , H 5 O 2 + Cl − , and H 5 O 2 + Cl − *H 2 O have been identified in these reaction systems.