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Title: Performance of SCAN density functional for a set of ionic liquid ion pairs

Authors:
ORCiD logo [1]; ORCiD logo [1];  [1];  [2]; ORCiD logo [1]
  1. Institute of Chemistry, University of Tartu, Ravila 14a, Tartu 50411 Estonia
  2. Department of Physics and Engineering Physics, Tulane University, New Orleans LA 70118
Publication Date:
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1415505
Grant/Contract Number:
SC0012575
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
International Journal of Quantum Chemistry
Additional Journal Information:
Related Information: CHORUS Timestamp: 2018-01-03 11:06:34; Journal ID: ISSN 0020-7608
Publisher:
Wiley Blackwell (John Wiley & Sons)
Country of Publication:
United States
Language:
English

Citation Formats

Karu, Karl, Mišin, Maksim, Ers, Heigo, Sun, Jianwei, and Ivaništšev, Vladislav. Performance of SCAN density functional for a set of ionic liquid ion pairs. United States: N. p., 2018. Web. doi:10.1002/qua.25582.
Karu, Karl, Mišin, Maksim, Ers, Heigo, Sun, Jianwei, & Ivaništšev, Vladislav. Performance of SCAN density functional for a set of ionic liquid ion pairs. United States. doi:10.1002/qua.25582.
Karu, Karl, Mišin, Maksim, Ers, Heigo, Sun, Jianwei, and Ivaništšev, Vladislav. 2018. "Performance of SCAN density functional for a set of ionic liquid ion pairs". United States. doi:10.1002/qua.25582.
@article{osti_1415505,
title = {Performance of SCAN density functional for a set of ionic liquid ion pairs},
author = {Karu, Karl and Mišin, Maksim and Ers, Heigo and Sun, Jianwei and Ivaništšev, Vladislav},
abstractNote = {},
doi = {10.1002/qua.25582},
journal = {International Journal of Quantum Chemistry},
number = ,
volume = ,
place = {United States},
year = 2018,
month = 1
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on January 3, 2019
Publisher's Accepted Manuscript

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  • We report details of the coordination environment about Cu(II) in a pure ionic liquid, 1- ethyl-3-methylimidazolium chloride ([EMIM]Cl) and in mixtures containing varying amounts of water from 0-100% of the [EMIM]Cl. There are many stages in the ion pairing of the divalent cation, Cu(II) including the contact ion pairing of Cu2+ with multiple Cl- to form various CuCln (2-n) polyanions. Thereis also the subsequent solvation and ion pairing of the polychlorometallate anion with the EMIM+ cation. Using a combination of x-ray absorption fine structure (XAFS), UV-Vis spectroscopy and electronic structure calculations (TDDFT) we are able to follow the detailed structuralmore » changes about Cu(II). Ion pair formation is strongly promoted in [EMIM]Cl by the low dielectric constant and by the extensive breakdown of the water hydrogen bond network in [EMIM]Cl/water mixtures. In the [EMIM]Cl solvent the CuCl4 2- species dominates and it’s geometry is quite similar to gas-phase structure. These results are important in understanding catalysis and separation processes involving transition metals in ionic liquid systems.« less
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  • In this work we present a study of the excitation energies of adenine, cytosine, guanine, thymine and the adenine-thymine (AT) and guanine-cytosine (GC) base pairs using long-range corrected (LC) density functional theory. We compare three recent LC-functionals, BNL, CAM-B3LYP and LC-PBE0 with B3LYP and coupled cluster results from the literature. We find that the best overall performance is for the BNL functional based on LDA. However, in order to achieve this good agreement a smaller attenuation parameter was needed which leads to non-optimum performance for ground state properties. B3LYP, on the other hand, severely underestimates the charge transfer (CT) transitionsmore » in the base pairs. Surprisingly we also find that the CAM-B3LYP functional also underestimates the CT excitation energy for the GC base pair, but correctly describes the AT base pair. This illustrates the importance of retaining the full long-range exact exchange even at distances as short as that of the DNA base pairs. The worst overall performance was obtained with the LC-PBE0 functional which overestimates the excitations for the individual bases as well as the base pairs. It is therefore crucial to strike a good balance between the amount of local and long-range exact exchange.« less