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Niskanen, J., Fondell, M., Sahle, C. J., Eckert, S., Jay, R. M., Gilmore, K., . . . Foehlisch, A. (2019). Compatibility of quantitative X-ray spectroscopy with continuous distribution models of water at ambient conditions. Proceedings of the National Academy of Sciences of the United States of America, 116(10), 4058-4063
Öppna denna publikation i ny flik eller fönster >>Compatibility of quantitative X-ray spectroscopy with continuous distribution models of water at ambient conditions
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2019 (Engelska)Ingår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 116, nr 10, s. 4058-4063Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The phase diagram of water harbors controversial views on underlying structural properties of its constituting molecular moieties, its fluctuating hydrogen-bonding network, as well as pair-correlation functions. In this work, long energy-range detection of the X-ray absorption allows us to unambiguously calibrate the spectra for water gas, liquid, and ice by the experimental atomic ionization cross-section. In liquid water, we extract the mean value of 1.74 +/- 2.1% donated and accepted hydrogen bonds per molecule, pointing to a continuous-distribution model. In addition, resonant inelastic X-ray scattering with unprecedented energy resolution also supports continuous distribution of molecular neighborhoods within liquid water, as do X-ray emission spectra once the femtosecond scattering duration and proton dynamics in resonant X-ray-matter interaction are taken into account. Thus, X-ray spectra of liquid water in ambient conditions can be understood without a two-structure model, whereas the occurrence of nanoscale-length correlations within the continuous distribution remains open.

Ort, förlag, år, upplaga, sidor
NATL ACAD SCIENCES, 2019
Nyckelord
structure of water, X-ray spectroscopy, continuous distribution model
Nationell ämneskategori
Kemi
Identifikatorer
urn:nbn:se:kth:diva-247814 (URN)10.1073/pnas.1815701116 (DOI)000460242100026 ()30782822 (PubMedID)2-s2.0-85062462267 (Scopus ID)
Anmärkning

QC 20190327

Tillgänglig från: 2019-03-27 Skapad: 2019-03-27 Senast uppdaterad: 2019-05-16Bibliografiskt granskad
da Cruz, V. V., Ignatova, N., Couto, R. C., Fedotov, D. A., Rehn, D. R., Savchenko, V., . . . Kimberg, V. (2019). Nuclear dynamics in resonant inelastic X-ray scattering and X-ray absorption of methanol. Journal of Chemical Physics, 150(23), Article ID 234301.
Öppna denna publikation i ny flik eller fönster >>Nuclear dynamics in resonant inelastic X-ray scattering and X-ray absorption of methanol
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2019 (Engelska)Ingår i: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 150, nr 23, artikel-id 234301Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

We report on a combined theoretical and experimental study of core-excitation spectra of gas and liquid phase methanol as obtained with the use of X-ray absorption spectroscopy (XAS) and resonant inelastic X-ray scattering (RIXS). The electronic transitions are studied with computational methods that include strict and extended second-order algebraic diagrammatic construction [ADC(2) and ADC(2)-x], restricted active space second-order perturbation theory, and time-dependent density functional theory-providing a complete assignment of the near oxygen K-edge XAS. We show that multimode nuclear dynamics is of crucial importance for explaining the available experimental XAS and RIXS spectra. The multimode nuclear motion was considered in a recently developed "mixed representation" where dissociative states and highly excited vibrational modes are accurately treated with a time-dependent wave packet technique, while the remaining active vibrational modes are described using Franck-Condon amplitudes. Particular attention is paid to the polarization dependence of RIXS and the effects of the isotopic substitution on the RIXS profile in the case of dissociative core-excited states. Our approach predicts the splitting of the 2a RIXS peak to be due to an interplay between molecular and pseudo-atomic features arising in the course of transitions between dissociative core- and valence-excited states. The dynamical nature of the splitting of the 2a peak in RIXS of liquid methanol near pre-edge core excitation is shown. The theoretical results are in good agreement with our liquid phase measurements and gas phase experimental data available from the literature.

Ort, förlag, år, upplaga, sidor
American Institute of Physics (AIP), 2019
Nationell ämneskategori
Fysikalisk kemi
Identifikatorer
urn:nbn:se:kth:diva-255315 (URN)10.1063/1.5092174 (DOI)000472600300006 ()31228920 (PubMedID)2-s2.0-85067465364 (Scopus ID)
Anmärkning

QC 20190807

Tillgänglig från: 2019-08-07 Skapad: 2019-08-07 Senast uppdaterad: 2019-12-20Bibliografiskt granskad
da Cruz, V. V., Gel'mukhanov, F., Eckert, S., Iannuzzi, M., Ertan, E., Pietzsch, A., . . . Odelius, M. (2019). Probing hydrogen bond strength in liquid water by resonant inelastic X-ray scattering. Nature Communications, 10, Article ID 1013.
Öppna denna publikation i ny flik eller fönster >>Probing hydrogen bond strength in liquid water by resonant inelastic X-ray scattering
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2019 (Engelska)Ingår i: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 10, artikel-id 1013Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Local probes of the electronic ground state are essential for understanding hydrogen bonding in aqueous environments. When tuned to the dissociative core-excited state at the O1s pre-edge of water, resonant inelastic X-ray scattering back to the electronic ground state exhibits a long vibrational progression due to ultrafast nuclear dynamics. We show how the coherent evolution of the OH bonds around the core-excited oxygen provides access to high vibrational levels in liquid water. The OH bonds stretch into the long-range part of the potential energy curve, which makes the X-ray probe more sensitive than infra-red spectroscopy to the local environment. We exploit this property to effectively probe hydrogen bond strength via the distribution of intramolecular OH potentials derived from measurements. In contrast, the dynamical splitting in the spectral feature of the lowest valence-excited state arises from the short-range part of the OH potential curve and is rather insensitive to hydrogen bonding.

Ort, förlag, år, upplaga, sidor
NATURE PUBLISHING GROUP, 2019
Nationell ämneskategori
Teoretisk kemi
Identifikatorer
urn:nbn:se:kth:diva-246231 (URN)10.1038/s41467-019-08979-4 (DOI)000460125000002 ()30833573 (PubMedID)2-s2.0-85062425511 (Scopus ID)
Anmärkning

QC 20190403

Tillgänglig från: 2019-04-03 Skapad: 2019-04-03 Senast uppdaterad: 2019-12-20Bibliografiskt granskad
Niskanen, J., Fondell, M., Sahle, C. J., Eckert, S., Jay, R. M., Gilmore, K., . . . Foehlisch, A. (2019). REPLY TO PETTERSSON ET AL.: Why X-ray spectral features are compatible to continuous distribution models in ambient water [Letter to the editor]. Proceedings of the National Academy of Sciences of the United States of America, 116(35), 17158-17159
Öppna denna publikation i ny flik eller fönster >>REPLY TO PETTERSSON ET AL.: Why X-ray spectral features are compatible to continuous distribution models in ambient water
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2019 (Engelska)Ingår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 116, nr 35, s. 17158-17159Artikel i tidskrift, Letter (Refereegranskat) Published
Ort, förlag, år, upplaga, sidor
NATL ACAD SCIENCES, 2019
Nationell ämneskategori
Teoretisk kemi
Identifikatorer
urn:nbn:se:kth:diva-259440 (URN)10.1073/pnas.1909551116 (DOI)000483396800007 ()31431526 (PubMedID)2-s2.0-85071402351 (Scopus ID)
Anmärkning

QC 20190923

Tillgänglig från: 2019-09-23 Skapad: 2019-09-23 Senast uppdaterad: 2019-09-23Bibliografiskt granskad
da Cruz, V. V., Ertan, E., Ignatova, N., Couto, R. C., Polyutov, S., Odelius, M., . . . Gel'mukhanov, F. (2018). Anomalous polarization dependence in vibrationally resolved resonant inelastic x-ray scattering of H2O. Physical Review A: covering atomic, molecular, and optical physics and quantum information, 98(1), Article ID 012507.
Öppna denna publikation i ny flik eller fönster >>Anomalous polarization dependence in vibrationally resolved resonant inelastic x-ray scattering of H2O
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2018 (Engelska)Ingår i: Physical Review A: covering atomic, molecular, and optical physics and quantum information, ISSN 2469-9926, E-ISSN 2469-9934, Vol. 98, nr 1, artikel-id 012507Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

It is well established that different electronic channels, in resonant inelastic x-ray scattering (RIXS), display different polarization dependences due to different orientations of their corresponding transition dipole moments in the molecular frame. However, this effect does not influence the vibrational progression in the Franck-Condon approximation. We have found that the transition dipole moments of core excitation and deexcitation experience ultrafast rotation during dissociation in the intermediate core-excited state. This rotation makes the vibrational progression in RIXS sensitive to the polarization of the x-ray photons. We study the water molecule, in which the effect is expressed in RIXS through the dissociative core-excited state where the vibrational scattering anisotropy is accompanied also by violation of parity selection rules for the vibrations.

Ort, förlag, år, upplaga, sidor
American Physical Society, 2018
Nationell ämneskategori
Fysik
Identifikatorer
urn:nbn:se:kth:diva-232763 (URN)10.1103/PhysRevA.98.012507 (DOI)000439279500006 ()2-s2.0-85050471678 (Scopus ID)
Forskningsfinansiär
VetenskapsrådetKnut och Alice Wallenbergs Stiftelse, KAW-2013.0020Carl Tryggers stiftelse för vetenskaplig forskning
Anmärkning

QC 20180803

Tillgänglig från: 2018-08-03 Skapad: 2018-08-03 Senast uppdaterad: 2019-12-20Bibliografiskt granskad
Ertan, E., Savchenko, V., Ignatova, N., da Cruz, V. V., Couto, R. C., Eckert, S., . . . Kimberg, V. (2018). Ultrafast dissociation features in RIXS spectra of the water molecule. Physical Chemistry, Chemical Physics - PCCP
Öppna denna publikation i ny flik eller fönster >>Ultrafast dissociation features in RIXS spectra of the water molecule
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2018 (Engelska)Ingår i: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

In this combined theoretical and experimental study we report on an analysis of the resonant inelastic X-ray scattering spectra (RIXS) of gas phase water via the lowest dissociative core-excited state |1sO-14a11〉. We focus on the spectral feature near the dissociation limit of the electronic ground state. We show that the narrow atomic-like peak consists of the overlapping contribution from the RIXS channels back to the ground state and to the first valence excited state |1b1-14a11〉 of the molecule. The spectral feature has signatures of ultrafast dissociation (UFD) in the core-excited state, as we show by means of ab initio calculations and time-dependent nuclear wave packet simulations. We show that the electronically elastic RIXS channel gives substantial contribution to the atomic-like resonance due to the strong bond length dependence of the magnitude and orientation of the transition dipole moment. By studying the RIXS for an excitation energy scan over the core-excited state resonance, we can understand and single out the molecular and atomic-like contributions in the decay to the lowest valence-excited state. Our study is complemented by a theoretical discussion of RIXS in the case of the isotope substituted water (HDO and D2O) where the nuclear dynamics is significantly affected by the heavier fragments' mass.

Nyckelord
resonant inelastic X-ray scattering, water molecule, Ultrafast dissociation, valence excited state, core-excited state
Nationell ämneskategori
Atom- och molekylfysik och optik
Forskningsämne
Kemi; Fysik
Identifikatorer
urn:nbn:se:kth:diva-227942 (URN)10.1039/C8CP01807C (DOI)000434246300010 ()2-s2.0-85048446772 (Scopus ID)
Anmärkning

QC 20180516

Tillgänglig från: 2018-05-15 Skapad: 2018-05-15 Senast uppdaterad: 2019-12-20Bibliografiskt granskad
Vaz da Cruz, V., Ertan, E., C. Couto, R., Eckert, S., Fondell, M., Dantz, M., . . . Kimberg, V. (2017). A study of the water molecule using frequency control over nuclear dynamics in resonant X-ray scattering. Physical Chemistry, Chemical Physics - PCCP, 19(30), 19573-19589
Öppna denna publikation i ny flik eller fönster >>A study of the water molecule using frequency control over nuclear dynamics in resonant X-ray scattering
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2017 (Engelska)Ingår i: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 19, nr 30, s. 19573-19589Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

In this combined theoretical and experimental study we report a full analysis of the resonant inelastic X-ray scattering (RIXS) spectra of H2O, D2O and HDO. We demonstrate that electronically-elastic RIXS has an inherent capability to map the potential energy surface and to perform vibrational analysis of the electronic ground state in multimode systems. We show that the control and selection of vibrational excitation can be performed by tuning the X-ray frequency across core-excited molecular bands and that this is clearly reflected in the RIXS spectra. Using high level ab initio electronic structure and quantum nuclear wave packet calculations together with high resolution RIXS measurements, we discuss in detail the mode coupling, mode localization and anharmonicity in the studied systems.

Ort, förlag, år, upplaga, sidor
Royal Society of Chemistry, 2017
Nyckelord
RIXS, water, quantum dynamics, x-ray
Nationell ämneskategori
Atom- och molekylfysik och optik
Forskningsämne
Teoretisk kemi och biologi
Identifikatorer
urn:nbn:se:kth:diva-187012 (URN)10.1039/C7CP01215B (DOI)000407053000006 ()28352891 (PubMedID)2-s2.0-85027313711 (Scopus ID)
Forskningsfinansiär
Knut och Alice Wallenbergs Stiftelse, KAW-2013.0020Carl Tryggers stiftelse för vetenskaplig forskning , CTS 15:266Vetenskapsrådet
Anmärkning

QC 20160516

Tillgänglig från: 2016-05-16 Skapad: 2016-05-16 Senast uppdaterad: 2019-12-20Bibliografiskt granskad
C. Couto, R., Vaz da Cruz, V., Ertan, E., Eckert, S., Fondell, M., Dantz, M., . . . Föhlisch, A. (2017). Selective gating to vibrational modes through resonant X-ray scattering [Letter to the editor]. Nature Communications, 8, 14165-1-14165-7
Öppna denna publikation i ny flik eller fönster >>Selective gating to vibrational modes through resonant X-ray scattering
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2017 (Engelska)Ingår i: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 8, s. 14165-1-14165-7Artikel i tidskrift, Letter (Refereegranskat) Published
Abstract [en]

The dynamics of fragmentation and vibration of molecular systems with a large number of coupled degrees of freedom are key aspects for understanding chemical reactivity and properties. Here we present a resonant inelastic X-ray scattering (RIXS) study to show how it is possible to break down such a complex multidimensional problem into elementary components. Local multimode nuclear wave packets created by X-ray excitation to different core-excited potential energy surfaces (PESs) will act as spatial gates to selectively probe the particular ground-state vibrational modes and, hence, the PES along these modes. We demonstrate this principle by combining ultra-high resolution RIXS measurements for gas-phase water with state-of-the-art simulations.

Ort, förlag, år, upplaga, sidor
Macmillan Publishers Ltd., 2017
Nyckelord
water, resonant inelastic x-ray scattering, vibrational modes, RIXS
Nationell ämneskategori
Atom- och molekylfysik och optik Teoretisk kemi
Forskningsämne
Teoretisk kemi och biologi
Identifikatorer
urn:nbn:se:kth:diva-187011 (URN)10.1038/ncomms14165 (DOI)000392541700001 ()2-s2.0-85009990586 (Scopus ID)
Forskningsfinansiär
Knut och Alice Wallenbergs Stiftelse, KAW-2013.0020Carl Tryggers stiftelse för vetenskaplig forskning , CTS 15:266Carl Tryggers stiftelse för vetenskaplig forskning , CTS 14:355Vetenskapsrådet, C0334701Vetenskapsrådet, 2015-03781Vetenskapsrådet, 2015-03956Vetenskapsrådet, 2015-04510EU, Horisont 2020, 669531 EDAX
Anmärkning

QC 20170123

Tillgänglig från: 2016-05-16 Skapad: 2016-05-16 Senast uppdaterad: 2019-12-20Bibliografiskt granskad
Savchenko, V., Zimin, A., Ignatova, N. Y., Kimberg, V., Gelmukhanov, F. & Polyutov, S. P. (2017). Size-dependent blinking of molecular aggregate total emission. In: 4th International School and Conference "Saint Petersburg OPEN 2017" on Optoelectronics, Photonics, Engineering and Nanostructures: . Paper presented at 4th International School and Conference "Saint Petersburg OPEN 2017" on Optoelectronics, Photonics, Engineering and Nanostructures, St. Petersburg Academic UniversitySaint-Petersburg, Russian Federation, 3 April 2017 through 6 April 2017. Institute of Physics Publishing (IOPP), 917(6), Article ID 062051.
Öppna denna publikation i ny flik eller fönster >>Size-dependent blinking of molecular aggregate total emission
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2017 (Engelska)Ingår i: 4th International School and Conference "Saint Petersburg OPEN 2017" on Optoelectronics, Photonics, Engineering and Nanostructures, Institute of Physics Publishing (IOPP), 2017, Vol. 917, nr 6, artikel-id 062051Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

Molecular aggregates are well known for their customizable optical properties. Vibronic coupling in monomers forming such aggregates offers rich opportunities for property tuning. We study generic molecular aggregate models of growing complexity (from a dimer up to a decamer) and report how vibronic coupling affects aggregate fluorescence intensity. The total aggregate fluorescence intensity is a measure sensitive to both vibronic coupling and Coulomb coupling between monomer transition densities. Using an exact diagonalization approach in the two-particle basis set, we show how the interplay between Coulomb and vibronic coupling affects aggregate fluorescence. Moreover, for H-aggregates we predict a periodic variation of the fluorescence intensity with aggregate size and show that vibronic interaction decreases the effect.

Ort, förlag, år, upplaga, sidor
Institute of Physics Publishing (IOPP), 2017
Serie
Journal of Physics Conference Series, ISSN 1742-6588 ; 917
Nationell ämneskategori
Fysikalisk kemi
Identifikatorer
urn:nbn:se:kth:diva-219893 (URN)10.1088/1742-6596/917/6/062051 (DOI)000423729100162 ()2-s2.0-85036476662 (Scopus ID)
Konferens
4th International School and Conference "Saint Petersburg OPEN 2017" on Optoelectronics, Photonics, Engineering and Nanostructures, St. Petersburg Academic UniversitySaint-Petersburg, Russian Federation, 3 April 2017 through 6 April 2017
Anmärkning

QC 20171215

Tillgänglig från: 2017-12-15 Skapad: 2017-12-15 Senast uppdaterad: 2018-02-22Bibliografiskt granskad
Ertan, E., Kimberg, V., Gel'mukhanov, F., Hennies, F., Rubensson, J.-E., Schmitt, T., . . . Pietzsch, A. (2017). Theoretical simulations of oxygen K-edge resonant inelastic x-ray scattering of kaolinite. Physical Review B, 95(14), Article ID 144301.
Öppna denna publikation i ny flik eller fönster >>Theoretical simulations of oxygen K-edge resonant inelastic x-ray scattering of kaolinite
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2017 (Engelska)Ingår i: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 95, nr 14, artikel-id 144301Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Near-edge x-ray absorption fine structure (NEXAFS) and resonant inelastic x-ray scattering (RIXS) measurements at the oxygen K edge were combined with theoretical spectrum simulations, based on periodic density functional theory and nuclear quantum dynamics, to investigate the electronic structure and chemical bonding in kaolinite Al2Si2O5(OH)(4). We simulated NEXAFS spectra of all crystallographically inequivalent oxygen atoms in the crystal and RIXS spectra of the hydroxyl groups. Detailed insight into the ground-state potential energy surface of the electronic states involved in the RIXS process were accessed by analyzing the vibrational excitations, induced by the core excitation, in quasielastic scattering back to the electronic ground state. In particular, we find that the NEXAFS pre-edge is dominated by features related to OH groups within the silica and alumina sheets, and that the vibrational progression in RIXS can be used to selectively probe vibrational modes of this subclass of OH groups. The signal is dominated by the OH stretching mode, but also other lower vibrational degrees of freedom, mainly hindered rotational modes, contribute to the RIXS signal.

Ort, förlag, år, upplaga, sidor
American Physical Society, 2017
Nationell ämneskategori
Fysik
Identifikatorer
urn:nbn:se:kth:diva-208251 (URN)10.1103/PhysRevB.95.144301 (DOI)000399382500002 ()2-s2.0-85017112786 (Scopus ID)
Forskningsfinansiär
VetenskapsrådetCarl Tryggers stiftelse för vetenskaplig forskning EU, FP7, Sjunde ramprogrammetKnut och Alice Wallenbergs Stiftelse, KAW-2013.0020
Anmärkning

QC 20170626

Tillgänglig från: 2017-06-26 Skapad: 2017-06-26 Senast uppdaterad: 2017-11-29Bibliografiskt granskad
Organisationer
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0003-1269-8760

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