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BETA
Hermansson, Kersti, Professor
Alternative names
Publications (10 of 217) Show all publications
Kebede, G., Mitev, P. D., Broqvist, P., Kullgren, J. & Hermansson, K. (2018). Hydrogen-Bond Relations for Surface OH Species [Review]. The Journal of Physical Chemistry C, 122(9), 4849-4858
Open this publication in new window or tab >>Hydrogen-Bond Relations for Surface OH Species
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2018 (English)In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 122, no 9, p. 4849-4858Article, book review (Refereed) Published
Abstract [en]

This paper concerns thin water films and their hydrogen-bond patterns on ionic surfaces. As far as we are aware, this is the first time H-bond correlations for surface water and hydroxide species are presented in the literature while hydrogen-bond relations in the solid state have been scrutinized for at least five decades. Our data set, which was derived using density functional theory, consists of 116 unique surface OH groups–intact water molecules as well as hydroxides–on MgO(001), CaO(001) and NaCl(001), covering the whole range from strong to weak to no H-bonds. The intact surface water molecules are found to always be redshifted with respect to the gas-phase water OH vibrational frequency, whereas the surface hydroxide groups are either redshifted (OsH) or blueshifted (OHf) compared to the gas-phase OH frequency. The surface H-bond relations are compared with the traditional relations for bulk crystals. We find that the “ν(OH) vs R(H···O)” correlation curve for surface water does not coincide with the solid state curve: it is redshifted by about 200 cm–1 or more. The intact water molecules and hydroxide groups on the ionic surfaces essentially follow the same H-bond correlation curve.

Place, publisher, year, edition, pages
Uppsala: , 2018
National Category
Physical Chemistry
Identifiers
urn:nbn:se:uu:diva-347220 (URN)10.1021/acs.jpcc.7b10981 (DOI)000427331300013 ()
Funder
Swedish Research Council
Available from: 2018-03-27 Created: 2018-03-27 Last updated: 2018-05-31Bibliographically approved
Kim, B.-H., Park, M., Kim, G., Hermansson, K., Broqvist, P., Choi, H.-J. & Lee, K.-R. (2018). Indirect-to-Direct Band Gap Transition of Si Nanosheets: Effect of Biaxial Strain. The Journal of Physical Chemistry C, 122(27), 15297-15303
Open this publication in new window or tab >>Indirect-to-Direct Band Gap Transition of Si Nanosheets: Effect of Biaxial Strain
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2018 (English)In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 122, no 27, p. 15297-15303Article in journal (Refereed) Published
Abstract [en]

The effect of biaxial strain on the band structure of two-dimensional silicon nanosheets (Si NSs) with (111), (110), and (001) exposed surfaces was investigated by means of density functional theory calculations. For all the considered Si NSs, an indirect-to-direct band gap transition occurs as the lateral dimensions of Si NSs increase; that is, increasing lateral biaxial strain from compressive to tensile always enhances the direct band gap characteristics. Further analysis revealed the mechanism of the transition which is caused by preferential shifts of the conduction band edge at a specific k-point because of their bond characteristics. Our results explain a photoluminescence result of the (111) Si NSs [U. Kim et al., ACS Nano 2011,.5, 2176-2181] in terms of the plausible tensile strain imposed in the unoxidized inner layer by surface oxidation.

National Category
Materials Chemistry Physical Chemistry
Identifiers
urn:nbn:se:uu:diva-362012 (URN)10.1021/acs.jpcc.8b02239 (DOI)000439003600028 ()
Funder
The Swedish Foundation for International Cooperation in Research and Higher Education (STINT), KO2016-6901
Available from: 2018-10-05 Created: 2018-10-05 Last updated: 2018-10-05Bibliographically approved
Quaranta, V., Hellstroem, M., Behler, J., Kullgren, J., Mitev, P. D. & Hermansson, K. (2018). Maximally resolved anharmonic OH vibrational spectrum of the water/ZnO(10(1)over-bar0) interface from a high-dimensional neural network potential. Journal of Chemical Physics, 148(24), Article ID 241720.
Open this publication in new window or tab >>Maximally resolved anharmonic OH vibrational spectrum of the water/ZnO(10(1)over-bar0) interface from a high-dimensional neural network potential
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2018 (English)In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 148, no 24, article id 241720Article in journal (Refereed) Published
Abstract [en]

Unraveling the atomistic details of solid/liquid interfaces, e.g., by means of vibrational spectroscopy, is of vital importance in numerous applications, from electrochemistry to heterogeneous catalysis. Water-oxide interfaces represent a formidable challenge because a large variety of molecular and dissociated water species are present at the surface. Here, we present a comprehensive theoretical analysis of the anharmonic OH stretching vibrations at the water/ZnO(10 (1) over bar0) interface as a prototypical case. Molecular dynamics simulations employing a reactive high-dimensional neural network potential based on density functional theory calculations have been used to sample the interfacial structures. In the second step, one-dimensional potential energy curves have been generated for a large number of configurations to solve the nuclear Schrodinger equation. We find that (i) the ZnO surface gives rise to OH frequency shifts up to a distance of about 4 angstrom from the surface; (ii) the spectrum contains a number of overlapping signals arising from different chemical species, with the frequencies decreasing in the order v (adsorbed hydroxide) > v (non-adsorbed water) > v (surface hydroxide) > v (adsorbed water); (iii) stretching frequencies are strongly influenced by the hydrogen bond pattern of these interfacial species. Finally, we have been able to identify substantial correlations between the stretching frequencies and hydrogen bond lengths for all species.

Place, publisher, year, edition, pages
AMER INST PHYSICS, 2018
National Category
Physical Chemistry
Identifiers
urn:nbn:se:uu:diva-360445 (URN)10.1063/1.5012980 (DOI)000437190300023 ()29960340 (PubMedID)
Funder
Swedish Research Council
Available from: 2018-09-13 Created: 2018-09-13 Last updated: 2018-09-13Bibliographically approved
Krishna Ammothum Kandy, A., Kullgren, J., Hermansson, K. & Broqvist, P. (2017). Can water affect the shape of CeO2 nanopartiles?. In: : . Paper presented at Swedish e-Science Academy 2017.
Open this publication in new window or tab >>Can water affect the shape of CeO2 nanopartiles?
2017 (English)Conference paper, Poster (with or without abstract) (Other academic)
National Category
Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-338350 (URN)
Conference
Swedish e-Science Academy 2017
Available from: 2018-01-08 Created: 2018-01-08 Last updated: 2018-01-08
Broqvist, P., Kullgren, J., Zhang, C., Du, D., Hermansson, K., Kebede, G., . . . Mitev, P. D. (2017). Chemistry of Complex Materials. In: : . Paper presented at Swedish e-Science Academy 2017.
Open this publication in new window or tab >>Chemistry of Complex Materials
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2017 (English)Conference paper, Poster (with or without abstract) (Other academic)
National Category
Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-338355 (URN)
Conference
Swedish e-Science Academy 2017
Available from: 2018-01-08 Created: 2018-01-08 Last updated: 2018-01-08
Zukowski, S. R., Mitev, P. D., Hermansson, K. & Ben-Amotz, D. (2017). CO2 Hydration Shell Structure and Transformation [Letter to the editor]. Journal of Physical Chemistry Letters, 8(13), 2971-2975
Open this publication in new window or tab >>CO2 Hydration Shell Structure and Transformation
2017 (English)In: Journal of Physical Chemistry Letters, ISSN 1948-7185, E-ISSN 1948-7185, Vol. 8, no 13, p. 2971-2975Article in journal, Letter (Refereed) Published
Abstract [en]

The hydration-shell of CO2 is characterized using Raman multivariate curve resolution (Raman-MCR) spectroscopy combined with ab initio molecular dynamics (AIMD) vibrational density of states simulations, to validate our assignment of the experimentally observed high-frequency OH band to a weak hydrogen bond between water and CO2. Our results reveal that while the hydration-shell of CO2 is highly tetrahedral, it is also occasionally disrupted by the presence of entropically stabilized defects associated with the CO2-water hydrogen bond. Moreover, we find that the hydration-shell of CO2 undergoes a temperature-dependent structural transformation to a highly disordered (less tetrahedral) structure, reminiscent of the transformation that takes place at higher temperatures around much larger oily molecules. The biological significance of the CO2 hydration shell structural transformation is suggested by the fact that it takes place near physiological temperatures.

National Category
Theoretical Chemistry
Identifiers
urn:nbn:se:uu:diva-327953 (URN)10.1021/acs.jpclett.7b00971 (DOI)000405252600033 ()28598626 (PubMedID)
Funder
Swedish Research CouncileSSENCE - An eScience Collaboration
Available from: 2017-08-14 Created: 2017-08-14 Last updated: 2018-09-18Bibliographically approved
Mitev, P. D., Briels, W. & Hermansson, K. (2017). CO2 in water from experiment and calculations. In: : . Paper presented at Swedish e-Science Academy 2017.
Open this publication in new window or tab >>CO2 in water from experiment and calculations
2017 (English)Conference paper, Poster (with or without abstract) (Other academic)
National Category
Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-338361 (URN)
Conference
Swedish e-Science Academy 2017
Available from: 2018-01-08 Created: 2018-01-08 Last updated: 2018-01-08
Kebede, G. G., Spångberg, D., Mitev, P. D., Broqvist, P. & Hermansson, K. (2017). Comparing van der Waals DFT methods for water on NaCl(001) and MgO(001). Journal of Chemical Physics, 146, Article ID 064703.
Open this publication in new window or tab >>Comparing van der Waals DFT methods for water on NaCl(001) and MgO(001)
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2017 (English)In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 146, article id 064703Article in journal (Other (popular science, discussion, etc.)) Published
National Category
Theoretical Chemistry
Identifiers
urn:nbn:se:uu:diva-315592 (URN)10.1063/1.4971790 (DOI)000394577400037 ()28201901 (PubMedID)
Funder
Swedish Research CouncilSwedish National Infrastructure for Computing (SNIC)
Available from: 2017-02-15 Created: 2017-02-15 Last updated: 2018-04-11Bibliographically approved
Dennis Larsson, E., Pazoki, M., Hermansson, K. & Kullgren, J. (2017). Computational Green Chemistry. In: : . Paper presented at Swedish e-Science Academy 2017.
Open this publication in new window or tab >>Computational Green Chemistry
2017 (English)Conference paper, Poster (with or without abstract) (Other academic)
National Category
Materials Chemistry Physical Chemistry
Identifiers
urn:nbn:se:uu:diva-338360 (URN)
Conference
Swedish e-Science Academy 2017
Available from: 2018-01-08 Created: 2018-01-08 Last updated: 2018-01-08
Kullgren, J., Wolf, M. J., Mitev, P. D., Hermansson, K. & Briels, W. J. (2017). Defect cluster at the CeO2(111) surface: A combined DFT and Monte-Carlo study. In: : . Paper presented at Annual meeting of the Swedish Chemical Society Theoretical Chemistry Section, Göteborg 16-18 August.
Open this publication in new window or tab >>Defect cluster at the CeO2(111) surface: A combined DFT and Monte-Carlo study
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2017 (English)Conference paper, Oral presentation with published abstract (Other academic)
National Category
Theoretical Chemistry
Identifiers
urn:nbn:se:uu:diva-338316 (URN)
Conference
Annual meeting of the Swedish Chemical Society Theoretical Chemistry Section, Göteborg 16-18 August
Available from: 2018-01-08 Created: 2018-01-08 Last updated: 2018-01-12Bibliographically approved
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