IR and X-ray study of polymorphism in 1-alkyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imides.
The crystal structure of [C(n)mim]NTf(2) (n = 2, 4, 6) was studied for the first time simultaneously by X-ray diffraction method and IR spectroscopy. The temperature-dependent IR spectrum for crystalline [C(4)mim]NTf(2) was demonstrated to correlate with both the X-ray data and the calorimetric results obtained earlier. Therefore, it was found that IR spectroscopy is able to establish the correspondence between the X-ray and the calorimetric data in this case. The joint use of X-ray diffraction, IR spectroscopy, and quantum-chemical calculations allowed us to determine the structure of all [C(2)mim]NTf(2) crystalline modifications obtained earlier by adiabatic calorimetry measurements. Thus, a new approach for the future identification of ionic liquid crystal structure by use of temperature-dependent infrared spectroscopy is suggested and justified.
Paulechka
Y U
YU
Chemistry Faculty, Belarusian State University, 220030 Mink, Belarus. paulechka@bsu.by
Kabo
G J
GJ
Blokhin
A V
AV
Shaplov
A S
AS
Lozinskaya
E I
EI
Golovanov
D G
DG
Lyssenko
K A
KA
Korlyukov
A A
AA
Vygodskii
Ya S
YS