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 | Sciact - CRIS-system of Boreskov Institute of Catalysis

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 Full article

Journal

Journal of Physical Chemistry Letters
ISSN: 1948-7185

Output data

Year: 2020, Volume: 11, Number: 15, Pages: 6000-6006 Pages count : 7 DOI: 10.1021/acs.jpclett.0c01731

Tags

Salts, Glass transition, Solvents, Noncovalent interactions, Nuclear magnetic resonance spectroscopy

Authors

Khudozhitkov Alexander E. ^1,2 , Niemann Thomas ³ , Stange Peter ³ , Donoshita Masaki ⁴ , Stepanov Alexander G. ^1,2 , Kitagawa Hiroshi ⁴ , Kolokolov Daniil I. ^1,2 , Ludwig Ralf ^3,5,6

Affiliations

1	Boreskov Institute of Catalysis, Siberian Branch of Russian Academy of Sciences
2	Novosibirsk State University
3	Abteilung für Physikalische Chemie, Institut für Chemie, Universität Rostock, Dr.-Lorenz-Weg 2, 18059 Rostock, Germany
4	Division of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan
5	Department LL&M, University of Rostock, Albert-Einstein-Straße 25, 18059 Rostock, Germany
6	Leibniz-Institut für Katalyse an der Universität Rostock e.V., Albert-Einstein-Straße 29a, 18059 Rostock, Germany

Funding (5)

1	Federal Agency for Scientific Organizations	0303-2016-0003
2	German Research Foundation	LU 506 14-1
3	German Research Foundation	LU 506/14-2 (286149019)
4	Japan Science and Technology Agency	JPMJAC1501
5	Rostock University

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.

Khudozhitkov A.E. , Niemann T. , Stange P. , Donoshita M. , Stepanov A.G. , Kitagawa H. , Kolokolov D.I. , Ludwig R.
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
Journal of Physical Chemistry Letters. 2020. V.11. N15. P.6000-6006. DOI: 10.1021/acs.jpclett.0c01731 WOS Scopus РИНЦ ANCAN PMID OpenAlex

Submitted:	Jun 4, 2020
Accepted:	Jul 8, 2020
Published online:	Jul 8, 2020
Published print:	Aug 6, 2020

Web of science:	WOS:000562064500027
Scopus:	2-s2.0-85089613886
Elibrary:	45393358
Chemical Abstracts:	2020:1354379
Chemical Abstracts (print):	173:439004
PMID:	32640795
OpenAlex:	W3042080499

DB	Citing
Elibrary	9
Scopus	10
Web of science	8
OpenAlex	10