Cg. Jung et al., KINETICS OF SOLVATED ELECTRONS IN REACTION WITH HEXAMETHYLPHOSPHORIC TRIAMIDE, Journal of the Chemical Society. Faraday transactions, 91(21), 1995, pp. 3809-3812
Citations number
21
Categorie Soggetti
Chemistry Physical","Physics, Atomic, Molecular & Chemical
Solvated electrons, e(s)(-), have been generated in hexamethylphosphor
ic triamide (HMPA) by chemical and electrochemical means, When Na meta
l was used to release e(s)(-), two distinct bands, already reported in
the literature, appeared in the absorption spectrum of the solution,
which rapidly turned red-brown and decomposed according to irreproduci
ble complex kinetics which could not be analysed. When Li was used ins
tead of sodium, a single broad band extending into the IR region devel
oped and later decayed obeying consistently first-order kinetics in ab
sorbance. Kinetic rate constants are reported and half-lives at ambien
t temperature were about 1 h duration. A systematic study of the disap
pearance of solvated electrons in HMPA was carried out at several temp
eratures (from 7 to 27 degrees C) and an activation energy (85-89 kJ m
ol(-1)) is estimated both in the absence and in the presence of lithiu
m perchlorate. However, the overall reaction rate is markedly increase
d in the presence of Li+; a mechanism is proposed to account for this
lithium salt effect.