中文
相关论文

相关论文: Ice Ic without stacking disorder by evacuating hyd…

200 篇论文

Most ice in nature forms thanks to impurities which boost the exceedingly low nucleation rate of pure supercooled water. However, the microscopic details of ice nucleation on these substances remain largely unknown. Here, we have unraveled…

The reversible phase transition from hydrochloric-acid-doped ice VI to its hydrogen-ordered counterpart ice XV is followed using differential scanning calorimetry. Upon cooling at ambient pressure fast hydrogen ordering is observed at first…

材料科学 · 物理学 2016-05-10 Jacob J. Shephard , Christoph G. Salzmann

The D2O ice VI to ice XV hydrogen ordering phase transition at ambient pressure is investigated in detail with neutron diffraction. The lattice constants are found to be sensitive indicators for hydrogen ordering. The a and b lattice…

Our knowledge about the physical processes determining the activity of comets were mainly influenced by several extremely successful space missions, the predictions of theoretical models and the results of laboratory experiments. However,…

地球与行星天体物理 · 物理学 2015-05-27 Bastian Gundlach , Yuri Skorov , Jürgen Blum

Water ice's remarkable properties make it an important material across a range of disciplines. The combination of covalent and hydrogen bonds form a long-range lattice of oxygens, which hosts a disordered yet correlated hydrogen network. We…

Ice naturally forms in the disordered or ``amorphous'' state when accreted from vapor at temperatures and pressures found in the interstellar medium and in the frigid, low density outer regions of the Sun's protoplanetary disk. It is…

地球与行星天体物理 · 物理学 2022-09-14 Dina Prialnik , David Jewitt

We report a new hydrogen clathrate hydrate synthesized at 1.2 GPa and 298 K documented by single-crystal X-ray diffraction, Raman spectroscopy, and first-principles calculations. The oxygen sublattice of the new clathrate hydrate matches…

We present a model of the growth of water ice on silicate grains in the circumstellar envelopes of Asymptotic Giant Branch (AGB) stars and Red Super Giants. We consider the growth of ice by gas grain collisions, the thermal evaporation of…

天体物理学 · 物理学 2011-05-23 C. Dijkstra , C. Dominik , S. N. Hoogzaad , A. de Koter , M. Min

Deposition of water on aerosol particles contributes to ice cloud formation in the atmosphere with implications for the water cycle and climate on Earth. The heterogeneous ice nucleation process is influenced by physico-chemical properties…

化学物理 · 物理学 2013-09-13 Xiangrui Kong , Patrik U. Andersson , Erik S. Thomson , Jan B. C. Pettersson

It has been implicitly assumed that ices on grains in molecular clouds and proto planetary disks are formed by homogeneous layers regardless of their composition or crystallinity. To verify this assumption, we observed the H2O deposition…

Most experimentally known high-pressure ice phases have a body-centred cubic (bcc) oxygen lattice. Our atomistic simulations show that, amongst these bcc ice phases, ices VII, VII' and X are the same thermodynamic phase under different…

Water hydrogen bonding is extremely versatile; approximately 20 ice structures and several types of clathrate hydrate structures have been identified. These crystalline water structures form at temperatures below room temperature and/or at…

The phase diagram of ice Ih, II, and III is studied by a quasi-harmonic approximation. The results of this approach are compared to phase diagrams previously derived by thermodynamic integration using path integral and classical…

化学物理 · 物理学 2012-10-16 R. Ramirez , N. Neuerburg , C. P. Herrero

Water (H2O) ice is an important solid constituent of many astrophysical environments. To comprehend the role of such ices in the chemistry and evolution of dense molecular clouds and comets, it is necessary to understand the freeze-out,…

天体物理学 · 物理学 2009-11-06 Helen J. Fraser , Mark P. Collings , Martin R. S. McCoustra , David A. Williams

Water ice is one of the most abundant materials in dense molecular clouds and in the outer reaches of protoplanetary disks. In contrast to other materials (e.g., silicates) water ice is assumed to be stickier due to its higher specific…

地球与行星天体物理 · 物理学 2015-06-23 B. Gundlach , J. Blum

Water ice is important for the evolution and preservation of life. Identifying the distribution of water ice in debris disks is therefore of great interest in the field of astrobiology. Furthermore, icy dust grains are expected to play…

地球与行星天体物理 · 物理学 2019-09-18 Minjae Kim , Sebastian Wolf , Alexey Potapov , Harald Mutschke , Cornelia Jäger

Ice is a major component of astrophysical environment - from interstellar molecular clouds through protoplanetary disks to evolved solar systems. Ice and complex organic matter coexist in these environments as well, and it is thought…

地球与行星天体物理 · 物理学 2023-07-27 Murthy S. Gudipati , Benjamin Fleury , Robert Wagner , Bryana L. Henderson , Kathrin Altwegg , Martin Rubin

Three properties of the dielectric relaxation in ultra-pure single crystalline H$_{2}$O ice Ih were probed at temperatures between 80-250 K; the thermally stimulated depolarization current, static electrical conductivity, and dielectric…

材料科学 · 物理学 2017-04-12 David T. W. Buckingham , John J. Neumeier , V. Hugo Schmidt

Machine learning models are rapidly becoming widely used to simulate complex physicochemical phenomena with ab initio accuracy. Here, we use one such model as well as direct density functional theory (DFT) calculations to investigate the…

We theoretically study the stability conditions of the ferroelectric ice of the Cmc21 structure, which has been considered, for decades, one of the most promising candidates of the low temperature proton-ordered phase of pure ice Ih. It…

材料科学 · 物理学 2010-07-13 Toshiaki Iitaka