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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Reactions of NO 3 with aromatic aldehydes: gas-phase kinetics and insights into the mechanism of the reaction

Rate coefficients for the reaction of NO3 radicals with a series of aromatic aldehydes were measured in a 7300 L simulation chamber at ambient temperature and pressure by relative and absolute methods. The rate coefficients for benzaldehyde (BA), ortho-tolualdehyde (O-TA), meta-tolualdehyde (M-TA), para-tolualdehyde (P-TA), 2,4-dimethyl benzaldehyde (2,4-DMBA), 2,5-dimethyl benzaldehyde (2,5-DMBA) and 3,5-dimethyl benzaldehyde (3,5-DMBA) were k 1 = 2.6 ± 0.3, k 2 = 8.7 ± 0.8, k 3 = 4.9 ± 0.5, k 4 = 4.9 ± 0.4, k 5 = 15.1 ± 1.3, k 6 = 12.8 ± 1.2 and k 7 = 6.2 ± 0.6, respectively, in the units of 10 -15 cm 3 molec. -1 s -1 at 298 ± 2 K. The rate coefficient k 13 for the reaction of the NO 3 radical with deuterated benzaldehyde (benzaldehyde-d1) was found to be half that of k 1 . The end product of the reaction in an excess of NO 2 was measured to be C 6 H 5 C(O)O 2 NO 2 . Furthermore, theoretical calculations of aldehydic bond energies and reaction pathways indicate that the NO 3 radical reacts primarily with aromatic aldehydes through the abstraction of an aldehydic hydrogen atom. The atmospheric implications of the measured rate coefficients are briefly discussed.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Materials Data on TaP by Materials Project

TaP is alpha Niobium phosphide structured and crystallizes in the tetragonal I4_1/amd space group. The structure is two-dimensional and consists of four TaP sheets oriented in the (0, 0, 1) direction. Ta3+ is bonded in a square co-planar geometry to four equivalent P3- atoms. All Ta–P bond lengths are 2.48 Å. P3- is bonded in a square co-planar geometry to four equivalent Ta3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta2P by Materials Project

Ta2P crystallizes in the orthorhombic Pnnm space group. The structure is three-dimensional. there are six inequivalent Ta sites. In the first Ta site, Ta is bonded in a distorted T-shaped geometry to three P atoms. There are a spread of Ta–P bond distances ranging from 2.57–2.75 Å. In the second Ta site, Ta is bonded to five P atoms to form distorted edge-sharing TaP5 trigonal bipyramids. There are a spread of Ta–P bond distances ranging from 2.50–2.56 Å. In the third Ta site, Ta is bonded in a 4-coordinate geometry to four P atoms. There are a spread of Ta–P bond distances ranging from 2.49–2.73 Å. In the fourth Ta site, Ta is bonded in a 3-coordinate geometry to three P atoms. There are two shorter (2.51 Å) and one longer (2.64 Å) Ta–P bond lengths. In the fifth Ta site, Ta is bonded in a 4-coordinate geometry to five P atoms. There are a spread of Ta–P bond distances ranging from 2.56–3.05 Å. In the sixth Ta site, Ta is bonded in a 4-coordinate geometry to four P atoms. There are two shorter (2.56 Å) and two longer (2.60 Å) Ta–P bond lengths. There are three inequivalent P sites. In the first P site, P is bonded in a 8-coordinate geometry to eight Ta atoms. In the second P site, P is bonded to seven Ta atoms to form distorted edge-sharing PTa7 pentagonal bipyramids. In the third P site, P is bonded in a 9-coordinate geometry to nine Ta atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta3P by Materials Project

Ta3P crystallizes in the tetragonal P4_2/n space group. The structure is three-dimensional. there are three inequivalent Ta sites. In the first Ta site, Ta is bonded in a distorted bent 150 degrees geometry to two equivalent P atoms. There are one shorter (2.57 Å) and one longer (2.59 Å) Ta–P bond lengths. In the second Ta site, Ta is bonded in a 4-coordinate geometry to four equivalent P atoms. There are a spread of Ta–P bond distances ranging from 2.58–2.61 Å. In the third Ta site, Ta is bonded in a distorted bent 150 degrees geometry to two equivalent P atoms. There are one shorter (2.57 Å) and one longer (2.60 Å) Ta–P bond lengths. P is bonded in a 8-coordinate geometry to eight Ta atoms.

36 MATERIALS SCIENCE↗