The <i>p–T</i> dependency of the ice II crystal structure and the effect of helium inclusion

Lobban, C.; Finney, John; Kuhs, Werner F.

doi:10.1063/1.1495837

Cited by 65 publications

(77 citation statements)

References 20 publications

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“…The strong hydrogen bonding significantly elongates the H 2 S covalent bond, producing two unique S-H distances for a single molecule: 1.45 and 1.35 Å for the quasi-a and -b directions, respectively. This anisotropy is similar to that found in ice II, where stronger inter-ring hydrogen bonding produces elongated O-H covalent distances relative to those observed between ring layers [21]. A distribution of S-H distances is supported experimentally by the large range observed for S-H stretching frequencies.…”

Section: Gpasupporting

confidence: 73%

Novel Cooperative Interactions and Structural Ordering inH2S−H2

et al. 2011

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Hydrogen sulfide (H(2)S) and hydrogen (H(2)) crystallize into a 'guest-host' structure at 3.5 GPa and, at the initial formation pressure, the rotationally disordered component molecules exhibit weak van der Waals-type interactions. With increasing pressure, hydrogen bonding develops and strengthens between neighboring H(2)S molecules, reflected in a pronounced drop in S-H vibrational stretching frequency and also observed in first-principles calculations. At 17 GPa, an ordering process occurs where H(2)S molecules orient themselves to maximize hydrogen bonding and H(2) molecules simultaneously occupy a chemically distinct lattice site. Intermolecular forces in the H(2)S+H(2) system may be tuned with pressure from the weak hydrogen-bonding limit to the ordered hydrogen-bonding regime, resulting in a novel clathrate structure stabilized by cooperative interactions.

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Section: Gpasupporting

confidence: 73%

Novel Cooperative Interactions and Structural Ordering inH2S−H2

et al. 2011

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“…40,41 Ice II is a fully hydrogen-ordered form of ice with R3 space group symmetry. [42][43][44] It is the only phase of ice for which the hydrogendisordered counterpart is unknown; 45 upon heating, it transforms to either ice Ih, III, V, or VI depending on the pressure. Ice II has a hexagonal unit cell comprising 36 water molecules and four distinct types of hydrogen bonds of equal multiplicity.…”

Section: A Background: Ices Ih II V and Xiiimentioning

confidence: 99%

2D IR spectroscopy of high-pressure phases of ice

Tran

Cunha

Shephard

et al. 2017

The Journal of Chemical Physics

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We present experimental and simulated 2D IR spectra of some high-pressure forms of isotope-pure D 2 O ice and compare the results to those of ice Ih published previously [F. Perakis and P. Hamm, Phys. Chem. Chem. Phys. 14, 6250 (2012); L. Shi et al., ibid. 18, 3772 (2016)]. Ice II, ice V, and ice XIII have been chosen for this study, since this selection covers many aspects of the polymorphism of ice. That is, ice II is a hydrogen-ordered phase of ice, in contrast to ice Ih, while ice V and ice XIII are a hydrogen-disordered/ordered couple that shares essentially the same oxygen structure and hydrogenbonded network. For the transmission 2D IR spectroscopy, a novel method had to be developed for the preparation of ultrathin films (1-2 µm) of high-pressure ices with good optical quality. We also simulated 2D IR spectra based on molecular dynamics simulations connected to a vibrational exciton picture. These simulations agree with the experimental results in a semi-quantitative manner for ice II, while the same approach failed for ice V and ice XIII. From the perspective of 2D IR spectroscopy, ice II appears to be more inhomogeneously broadened than ice Ih, despite its hydrogen-order, which we attribute to the fact that ice II is structurally more complex with four distinguishable hydrogen bonds that mix due to exciton coupling. Ice V and ice XIII, on the other hand, behave as expected with the hydrogen-disordered case (ice V) being more inhomogenously broadened. Furthermore, in all hydrogen-ordered forms (ice II and ice XIII), cross peaks could be identified in the anisotropic 2D IR spectrum, whose signs reveal the relative direction of the corresponding excitonic states. Published by AIP Publishing. https://doi

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“…We have focused on proton ordered phases because they are more straightforward to model than the proton disordered phases. The initial structures used for the proton ordered phases have been obtained from experiment 85,[98][99][100][101][102] and the unit cells used are shown in Fig. 1.…”

Section: Simulation Detailsmentioning

confidence: 99%

On the accuracy of van der Waals inclusive density-functional theory exchange-correlation functionals for ice at ambient and high pressures

Santra¹,

Klimeš²,

Tkatchenko³

et al. 2013

The Journal of Chemical Physics

128

174

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On the accuracy of van der Waals inclusive density-functional theory exchange-correlation functionals for ice at ambient and high pressures Density-functional theory (DFT) has been widely used to study water and ice for at least 20 years. However, the reliability of different DFT exchange-correlation (xc) functionals for water remains a matter of considerable debate. This is particularly true in light of the recent development of DFT based methods that account for van der Waals (vdW) dispersion forces. Here, we report a detailed study with several xc functionals (semi-local, hybrid, and vdW inclusive approaches) on ice Ih and six proton ordered phases of ice. Consistent with our previous study [B. Santra, J. Klimeš, D. Alfè, A. Tkatchenko, B. Slater, A. Michaelides, R. Car, and M. Scheffler, Phys. Rev. Lett. 107, 185701 (2011)] which showed that vdW forces become increasingly important at high pressures, we find here that all vdW inclusive methods considered improve the relative energies and transition pressures of the high-pressure ice phases compared to those obtained with semi-local or hybrid xc functionals. However, we also find that significant discrepancies between experiment and the vdW inclusive approaches remain in the cohesive properties of the various phases, causing certain phases to be absent from the phase diagram. Therefore, room for improvement in the description of water at ambient and high pressures remains and we suggest that because of the stern test the high pressure ice phases pose they should be used in future benchmark studies of simulation methods for water. © 2013 AIP Publishing LLC. [http://dx

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The p–T dependency of the ice II crystal structure and the effect of helium inclusion

Cited by 65 publications

References 20 publications

Novel Cooperative Interactions and Structural Ordering inH2S−H2

Novel Cooperative Interactions and Structural Ordering inH2S−H2

2D IR spectroscopy of high-pressure phases of ice

On the accuracy of van der Waals inclusive density-functional theory exchange-correlation functionals for ice at ambient and high pressures

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