Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
Freezing the Motion in Hydroxy-Functionalized Ionic Liquids-Temperature Dependent NMR Deuteron Quadrupole Coupling Constants for Two Types of Hydrogen Bonds Far below the Glass Transition. / Khudozhitkov, Alexander E.; Niemann, Thomas; Stange, Peter и др.
в: The journal of physical chemistry letters, Том 11, № 15, 06.08.2020, стр. 6000-6006.Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
}
TY - JOUR
T1 - Freezing the Motion in Hydroxy-Functionalized Ionic Liquids-Temperature Dependent NMR Deuteron Quadrupole Coupling Constants for Two Types of Hydrogen Bonds Far below the Glass Transition
AU - Khudozhitkov, Alexander E.
AU - Niemann, Thomas
AU - Stange, Peter
AU - Donoshita, Masaki
AU - Stepanov, Alexander G.
AU - Kitagawa, Hiroshi
AU - Kolokolov, Daniil I.
AU - Ludwig, Ralf
N1 - Publisher Copyright: Copyright © 2020 American Chemical Society. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020/8/6
Y1 - 2020/8/6
N2 - We measured the deuteron quadrupole coupling constants (DQCCs) for hydroxy-functionalized ionic liquids (ILs) with varying alkyl chain length over the temperature range between 60 and 200 K by means of solid-state NMR spectroscopy. For all temperatures, the 2H spectra show two DQCCs representing different types of hydrogen bonds. Higher values, ranging from 220 to 250 kHz, indicate weaker hydrogen bonds between cation and anion (c-a), and lower values varying from 165 to 210 kHz result from stronger hydrogen bonds between the OD groups of cations (c-c), in agreement with recent observations in infrared, neutron diffraction, and NMR studies. We observed different temperature dependencies for (c-a) and (c-c) hydrogen bonding. From the static pattern of the 2H spectra at the lowest temperatures, we derived the true DQCCs being up to 20 kHz larger than recently reported values measured at the glass transition temperature. We were able to freeze the librational motions of the hydrogen bonds in the ILs. The temperature dependence of the (c-a) and (c-c) cluster populations in the glassy state is opposite to that observed in the liquid state, partly anticipating the behavior of ILs tending to crystallize.
AB - We measured the deuteron quadrupole coupling constants (DQCCs) for hydroxy-functionalized ionic liquids (ILs) with varying alkyl chain length over the temperature range between 60 and 200 K by means of solid-state NMR spectroscopy. For all temperatures, the 2H spectra show two DQCCs representing different types of hydrogen bonds. Higher values, ranging from 220 to 250 kHz, indicate weaker hydrogen bonds between cation and anion (c-a), and lower values varying from 165 to 210 kHz result from stronger hydrogen bonds between the OD groups of cations (c-c), in agreement with recent observations in infrared, neutron diffraction, and NMR studies. We observed different temperature dependencies for (c-a) and (c-c) hydrogen bonding. From the static pattern of the 2H spectra at the lowest temperatures, we derived the true DQCCs being up to 20 kHz larger than recently reported values measured at the glass transition temperature. We were able to freeze the librational motions of the hydrogen bonds in the ILs. The temperature dependence of the (c-a) and (c-c) cluster populations in the glassy state is opposite to that observed in the liquid state, partly anticipating the behavior of ILs tending to crystallize.
KW - NUCLEAR-MAGNETIC-RESONANCE
KW - CATIONIC CLUSTERS
KW - CHARGED IONS
KW - PROTON
KW - ELECTROLYTES
KW - EXTRACTION
KW - CRYSTALS
KW - TIME
KW - ICE
UR - http://www.scopus.com/inward/record.url?scp=85089613886&partnerID=8YFLogxK
U2 - 10.1021/acs.jpclett.0c01731
DO - 10.1021/acs.jpclett.0c01731
M3 - Article
C2 - 32640795
AN - SCOPUS:85089613886
VL - 11
SP - 6000
EP - 6006
JO - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
SN - 1948-7185
IS - 15
ER -
ID: 24985502