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We investigate switching of photoluminescence from PbS quantum dots crosslinked with photochromic diarylethene molecules with different degree of halogenation.
Ni(H2O)6(BH)12(H2)6(O2)3 crystallizes in the cubic F4_132 space group. The structure is zero-dimensional and consists of ninety-six boranediylradical molecules, forty-eight hydrogen molecules, eight nsvfpfuroxfzjs-uhfffaoysa-n molecules, and sixteen trioxirane molecules.
Lyman alpha radiation from electron collisions with simple H-containing molecules, finding dissociative excitation cross section role
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A statistical model, the local plasma approximation, is considered for the calculation of the logarithmic mean excitation energy for stopping power of chemically bound particles by taking into consideration chemical bonding. This statistical model is applied to molecular hydrogen and leads to results that suggest a value for the logarithmic mean excitation energy of molecular hydrogen that is larger than the accepted experimental and theoretical values.
H2S2O7 crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of four disulfuric acid molecules, four hydrogen peroxide molecules, four sulfino hydrogen sulfite molecules, and four H2S2O7 clusters. In each H2S2O7 cluster, there are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the second H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.66 Å) H–O bond length. There are two inequivalent S6+ sites. In the first S6+ site, S6+ is bonded to four O2- atoms to form corner-sharing SO4 tetrahedra. There are a spread of S–O bond distances ranging from 1.43–1.69 Å. In the second S6+ site, S6+ is bonded to four O2- atoms to form corner-sharing SO4 tetrahedra. There are a spread of S–O bond distances ranging from 1.42–1.63 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to two S6+ atoms. In the second O2- site, O2- is bonded in a single-bond geometry to one S6+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one S6+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one H1+ and one S6+ atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one H1+ and one S6+ atom. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to one H1+ and one S6+ atom. In the seventh O2- site, O2- is bonded in a single-bond geometry to one S6+ atom.
CaSn(S)3 crystallizes in the monoclinic C2 space group. The structure is zero-dimensional and consists of four 7440-31-5 molecules, four calcium molecules, four hydrogen disulfide molecules, and four hydrogen sulfide molecules.
Al(H2)6 is alpha carbon monoxide-like structured and crystallizes in the cubic Fd-3m space group. The structure is zero-dimensional and consists of eight aluminum molecules and forty-eight hydrogen molecules.
N2SS2O5 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of eight ammonia molecules, four hydrogen sulfide molecules, and four sulfino hydrogen sulfite molecules.
In the model of Hollenbach et al. (1971), hydrogen molecules are formed on grains. Molecular hydrogen is destroyed by absorption of radiation in the Lyman bands. A study has been conducted regarding the formation and destruction rates of molecular hydrogen. The ultraviolet radiation field has been calculated to determine the rate of molecular hydrogen destruction resulting from absorption in the Lyman bands. An estimate of an upper limit for the molecular hydrogen formation rate is obtained from observations involving stars in which very little molecular hydrogen is observed.
Continuous absorption in solar atmosphere by quasi-hydrogen molecule
Abstract Spatially resolved rotational temperature of ground state hydrogen molecules desorbed from plasma-facing surface was measured in QUEST, LTX-β, and DIII-D tokamaks, and the increases of the rotational temperature with the surface temperature and due to collisional-radiative processes in the plasmas were evaluated. The increase due to collisional-radiative processes was calculated by solving rate equations considering electron and proton collisional excitation and deexcitation and spontaneous emission. The calculation results suggest a high sensitivity for the rotational temperature to electron and proton densities, but a negligible sensitivity to the electron, proton, and surface temperatures. In the three tokamaks with different plasma parameters and plasma-facing surface materials, the spatial profile of the rotational temperature was estimated using Fulcher-α emission lines (600–608 nm). In QUEST, the spatial profile of the rotational temperature was estimated from spatially resolved spectra. In the other tokamaks, the rotational temperature was evaluated assuming a single point emission with a location determined from the Fulcher-α emission profile as measured with a filtered camera. In metal-walled devices QUEST and LTX-β, the rotational temperature increased with the surface temperature, and the calculated collisional-radiative increase is consistent with measured increase assuming that the rotational temperature at the surface is approximately 500–600 K higher than the surface temperature. In DIII-D with carbon walls, a larger collisional-radiative increase than the other tokamaks was observed because of the higher density leading to a large difference from the calculated increase compared to the other smaller tokamaks. Measurement of the Fulcher-α emission profile with higher spatial resolution in DIII-D may reduce the difference and reveal the effect of the surface temperature on the rotational temperature. These results show the increases in the rotational temperature with the surface temperature and due to the collisional-radiative processes.
Manipulating the insulator–metal transition in strongly correlated materials has attracted a broad range of research activity due to its promising applications in, for example, memories, electrochromic windows and optical modulators. Electric-field-controlled hydrogenation using ionic liquids and solid electrolytes is a useful strategy to obtain the insulator–metal transition with corresponding electron filling, but faces technical challenges for miniaturization due to the complicated device architecture. Here, in this work, we demonstrate reversible electric-field control of nanoscale hydrogenation into VO 2 with a tunable insulator–metal transition using a scanning probe. The Pt-coated probe serves as an efficient catalyst to split hydrogen molecules, while the positive-biased voltage accelerates hydrogen ions between the tip and sample surface to facilitate their incorporation, leading to non-volatile transformation from insulating VO 2 into conducting H x VO 2 . Remarkably, a negative-biased voltage triggers dehydrogenation to restore the insulating VO 2 . This work demonstrates a local and reversible electric-field-controlled insulator–metal transition through hydrogen evolution and presents a versatile pathway to exploit multiple functional devices at the nanoscale.
(BaTe(SO3)2)2(S)4(O2)3 crystallizes in the monoclinic P2_1/c space group. The structure is one-dimensional and consists of six hydrogen peroxide molecules; eight hydrogen sulfide molecules; and two BaTe(SO3)2 ribbons oriented in the (0, 1, 0) direction. In each BaTe(SO3)2 ribbon, Ba2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ba–O bond distances ranging from 2.62–3.20 Å. Te4+ is bonded in a distorted single-bond geometry to one O2- atom. The Te–O bond length is 2.87 Å. There are two inequivalent S3+ sites. In the first S3+ site, S3+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. All S–O bond lengths are 1.47 Å. In the second S3+ site, S3+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of S–O bond distances ranging from 1.46–1.49 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one Ba2+ and one S3+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Te4+ and one S3+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Ba2+ and one S3+ atom. In the fourth O2- site, O2- is bonded in a distorted water-like geometry to one Ba2+ and one S3+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ba2+ and one S3+ atom. In the sixth O2- site, O2- is bonded in a distorted linear geometry to one Ba2+ and one S3+ atom.
S30C crystallizes in the monoclinic C2/m space group. The structure is zero-dimensional and consists of twelve hydrogen disulfide molecules, eight hydrogen sulfide molecules, two CS2 clusters, and eight S clusters. In each CS2 cluster, C4+ is bonded in a linear geometry to two equivalent S+0.13- atoms. Both C–S bond lengths are 1.55 Å. S+0.13- is bonded in a single-bond geometry to one C4+ atom. In each S cluster, there are three inequivalent S+0.13- sites. In the first S+0.13- site, S+0.13- is bonded in a single-bond geometry to two S+0.13- atoms. There are one shorter (1.90 Å) and one longer (3.69 Å) S–S bond lengths. In the second S+0.13- site, S+0.13- is bonded in a single-bond geometry to two S+0.13- atoms. The S–S bond length is 3.85 Å. In the third S+0.13- site, S+0.13- is bonded in a 1-coordinate geometry to two S+0.13- atoms.
Approximation method using sum rules for energy shift in atomic system due to interaction of electrons with vacuum electromagnetic field applied to hydrogen, helium and lithium atom ground states and hydrogen molecule
Potential energy surfaces on triatomic hydrogen molecule ion computed with generalized Gaussian orbitals