State- and bond-selected photodissociation and bimolecular reaction of water

It is possible to exploit the isolation of the 0 —H stretching vibration in H 20 and HOD to control the photodissociation and reaction dynamics in water molecules excited in the region of the third overtone (4rOH) of the 0 -H stretch. In vibrationally mediated photodissociation of H 20, the selection of different initial stretching states having roughly the same energy leads to drastically different populations of the vibrational states of the OH photolysis product. By exciting the O-H stretching overtone in HOD, we can selectively photolyze that bond. In bimolecular reaction experiments, we react H 20 (4rOH) with H atoms to produce H 2 and OH. The reaction, which is endothermic, proceeds at an undetectable rate in our room temperature measurements. Vibrationally excited water, however, reacts at roughly the gas kinetic collision rate. Applying this technique to HOD (4rOH) allows us to demonstrate bond selected bimolecular chemistry in which the reaction produces only OD. This observation suggests a general approach to assessing bond controlled reactions in a variety of systems.

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A tentative interpretation of the results of recent X-ray and infra-red studies of liquid water and H 2 O + D 2 O mixtures

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1958.0205 ◽

1958 ◽

Vol 247 (1251) ◽

pp. 472-481 ◽

Cited By ~ 18

Keyword(s):

Liquid Water ◽

Room Temperature ◽

Water Molecules ◽

X Ray Diffraction ◽

X Ray ◽

Infra Red ◽

Stretching Vibration ◽

Density Of Water ◽

Absorption Measurements ◽

Melting Entropy

An idealized model is proposed for the arrangement of the molecules in liquid water which involves essentially a sixfold co-ordination of water molecules with four short OH...O hydrogen bonds of ~2.9 Å length and two long O...O contacts of ~3.6 Å length. An ice-like structure may contribute to a small extent also. This octahedral model has been based on evidence obtained from X-ray and infra-red absorption measurements. The model has been found to be in agreement with the density of water and the melting entropy of ice. The reliability of the radial distribution curves W(r) of liquid water obtained from recent X-ray diffraction measurements is discussed. Infra-red absorption measurements have been made of liquid HDO in excess D 2 O and H 2 O, respectively. The respective O—H and O—D stretching vibration frequencies of liquid HDO have been determined. The position (at 3400 cm -1 ) and shape of the relatively sharp single O—H stretching absorption band of liquid HDO is closely comparable to the corresponding band in liquid interbonding alcohols. The results of the infra-red studies indicate an OH...O distance of 2.86 Å in liquid water at room temperature.

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The Effect of Electron Irradiation on the Structure of Sodium Aluminum-Iron Phosphate Glasses

MRS Advances ◽

10.1557/adv.2017.213 ◽

2016 ◽

Vol 1 (63-64) ◽

pp. 4227-4232 ◽

Cited By ~ 2

Author(s):

S.V. Stefanovsky ◽

O.I. Stefanovsky ◽

M.I Kadyko ◽

V.A. Zhachkin ◽

L.D. Bogomolova

Keyword(s):

Room Temperature ◽

Structural Evolution ◽

Iron Phosphate ◽

Esr Spectra ◽

Phosphate Glasses ◽

Water Molecules ◽

Oxygen Hole ◽

Bending Modes ◽

Iron Phosphate Glasses ◽

Hole Centers

ABSTRACTGlasses of the series (mol.%) 40 Na2O, (20-x) Al2O3, x Fe2O3, 40 P2O5 were irradiated with 8 MeV electrons to doses equivalent of 0.1, 0.5, and 1.0 MGy and characterized by FTIR spectroscopy and ESR at room temperature. FTIR spectra of all the glasses consist of strong bands due to O-P-O stretching modes in (PO4)3- and (P2O7)4- units at 1000-1200 cm-1, P-O-P stretching modes at 900-950 cm-1 (νas) and 700-750 cm-1 (νs), and bending modes in the PO4 units. The wavenumber range lower 800 cm-1 has some contribution due to stretching modes in MO4 and MO6 (M = Al, Fe) units. Moreover the bands at 3300-3700 cm-1 and 1550-1650 cm-1 due to stretching and bending modes in both absorbed and structurally bound H2O molecules were present. As irradiation dose increases the bands due to stretching and bending modes in water molecules and M-O-H bonds become stronger and are split. No essential changes with increasing dose were observed within the spectral range of stretching modes of the O-P-O and P-O-P bonds. Irradiation yields phosphorus-oxygen hole centers - PO42- (D5) and PO42- (D6), and PO32- ion-radicals (D2) observable in ESR spectra of low-Fe glasses. At x>5 their responses are overlapped with strong broad line due to Fe(III). On the whole, with the increase in iron content the glass structural evolution decrease.

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Crystal structure of the new hybrid material bis(1,4-diazoniabicyclo[2.2.2]octane) di-μ-chlorido-bis[tetrachloridobismuthate(III)] dihydrate

Acta Crystallographica Section E Crystallographic Communications ◽

10.1107/s2056989015019933 ◽

2015 ◽

Vol 71 (11) ◽

pp. 1384-1387

Author(s):

Marwen Chouri ◽

Habib Boughzala

Keyword(s):

Crystal Structure ◽

Aqueous Solution ◽

Hydrogen Bonds ◽

Room Temperature ◽

Molar Ratio ◽

Water Molecules ◽

Site Symmetry ◽

Two Dimensional ◽

Slow Evaporation ◽

Solution Ph

The title compound bis(1,4-diazoniabicyclo[2.2.2]octane) di-μ-chlorido-bis[tetrachloridobismuthate(III)] dihydrate, (C6H14N2)2[Bi2Cl10]·2H2O, was obtained by slow evaporation at room temperature of a hydrochloric aqueous solution (pH = 1) containing bismuth(III) nitrate and 1,4-diazabicyclo[2.2.2]octane (DABCO) in a 1:2 molar ratio. The structure displays a two-dimensional arrangement parallel to (100) of isolated [Bi2Cl10]4−bioctahedra (site symmetry -1) separated by layers of organic 1,4-diazoniabicyclo[2.2.2]octane dications [(DABCOH2)2+] and water molecules. O—H...Cl, N—H...O and N—H...Cl hydrogen bonds lead to additional cohesion of the structure.

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Ein Wasserstoffisotopieeffekt im CuSO4 * 5H2O

Zeitschrift für Naturforschung A ◽

10.1515/zna-1969-1007 ◽

1969 ◽

Vol 24 (10) ◽

pp. 1502-1511

Author(s):

Karl Heinzinger

Keyword(s):

Water Vapor ◽

Aqueous Solutions ◽

Separation Factor ◽

Room Temperature ◽

Copper Ion ◽

Hydrogen Isotopes ◽

Bulk Water ◽

Water Molecules ◽

Hydration Water ◽

Sulfate Solutions

Abstract There are two kinds of water in CuSO4·5H2O differing by their binding in the crystal. The oxygen of four water molecules is bonded to the copper ion, that of the fifth molecule is hydrogen bonded. It is shown that the D/H ratios of these two kinds of water differ by 5.7%, the light isotope being enriched in the water molecules coordinated with the copper ion. The results show that there is no exchange of the hydrogen isotopes during the time needed for dehydration at room temperature which takes several days. The assumption has been confirmed that the water coordinated with the copper ion leaves the crystal first on dehydration at temperatures below 50 °C. Additional measurements of the separation factor for the hydrogen isotopes between water vapor and copper sulfate solutions allow conclusions on the fractionation of the hydrogen isotopes between bulk water and hydration water in aqueous solutions.

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A theoretical study on the C + OH reaction dynamics and product energy disposal with vibrationally excited reagent

The European Physical Journal D ◽

10.1140/epjd/e2018-90424-0 ◽

2018 ◽

Vol 72 (12) ◽

Author(s):

Sugata Goswami ◽

Jayakrushna Sahoo ◽

Tammineni Rajagopala Rao ◽

Béatrice Bussery-Honvault ◽

Pascal Honvault ◽

...

Keyword(s):

Theoretical Study ◽

Reaction Dynamics ◽

Vibrationally Excited

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INFRARED SPECTRA OF THIOSACCHARINATES OF CADMIUM AND LEAD COMPARISON WITH THE ANALOGOUS METAL SACCHARINATES

Contributions Section of Natural Mathematical and Biotechnical Sciences ◽

10.20903/csnmbs.masa.2006.27.1-2.10 ◽

2017 ◽

Vol 27 (1-2) ◽

Author(s):

Gligor Jovanovski ◽

Adnan Kahil ◽

Orhideja Grupče

Keyword(s):

Infrared Spectra ◽

Room Temperature ◽

Spectral Characteristics ◽

Crystalline Hydrate ◽

Water Molecules ◽

X Ray ◽

Weak Hydrogen Bonds ◽

Deuterated Analogue ◽

The Fourier Transform ◽

Cadmium And Lead

A b s t r a c t: The Fourier transform (FT) infrared spectra of thiosaccharinates of cadmium and lead in the 4000–400 cm–1 region were studied. Although the observed resemblance between the spectra recorded in KBr pellets suggests a possible similarity between their structures as well, the powder X-ray diagrams show that these two compounds are not isomorphous. The presence of broad and intense bands in the region of the HOH stretchings shows that thiosaccharinate of cadmium is a crystalline hydrate and the spectral picture in the region of the O-D stretchings of the isotopically isolated HOD molecules in the partially deuterated analogue indicates that present in its structure are at least two types of crystallographically different water molecules involved in the formation of weak hydrogen bonds. The room temperature (RT) spectrum of lead thiosaccharinate in the region of the ν(HOH) modes differs significantly from the spectrum recorded at the boiling temperature of liquid nitrogen (LNT), which may perhaps be interpreted as an indication that a phase transition is taking place on lowering the temperature. The spectrum of lead thiosaccharinate was recorded in a Nujol mull as well. While the KBr and Nujol spectra are essentially identical in the region below 1600 cm–1, no bands are observed in the HOH stretching region of the mull spectra. In fact, it was shown that the appearance of the spectra of lead thiosaccharinates depends on the emulsion preparation rate. A comparison of the spectral characteristics of the thiosaccharinates of cadmium and lead with those of the corresponding saccharinates (their crystal structures are known) was made, special attention being paid to the analysis of the SO2 stretching region in the saccharinate and thiosaccharinate compounds.

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Ultrafast infrared studies of chemical reaction dynamics in room-temperature liquids

10.2172/760337 ◽

1999 ◽

Author(s):

Haw Yang

Keyword(s):

Chemical Reaction ◽

Room Temperature ◽

Reaction Dynamics ◽

Infrared Studies ◽

Chemical Reaction Dynamics ◽

Ultrafast Infrared

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Das Kombinationsschwingungsspektrum von Gips im Bereich von 10 000—1200 cm-1

Zeitschrift für Naturforschung A ◽

10.1515/zna-1968-0514 ◽

1968 ◽

Vol 23 (5) ◽

pp. 708-715 ◽

Cited By ~ 2

Author(s):

V. Hohler ◽

H. D. Lutz

Keyword(s):

Hydrogen Bonds ◽

Ir Spectrum ◽

Room Temperature ◽

Polarized Light ◽

Water Molecules ◽

Lattice Vibrations ◽

Frequency Range ◽

Sulfate Ions ◽

Normal Vibrations

The IR-spectrum of gypsum (CaSO4·2 H2O) in the frequency range from 10 000 to 1200 cm-1 has been investigated with polarized light at room temperature. Between 3700 and 1200 cm-1, the measurements confirm the data of HASS and SUTHERLAND and as well as those of SCHAAK derived from IR and reflection measurements. The IR-spectrum shows a great number of bands, most of which can be assigned to combination and fundamental vibrations in terms of normal vibrations of the water molecules and the sulfate ions. The influence of the lattice vibrations is briefly discussed. The existence of hydrogen bonds between the water molecules and the sulfate ions gives rise to combinations of fundamental vibrations of both complexes.

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