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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Pt(NO3)2 by Materials Project

Pt(NO3)2 crystallizes in the triclinic P-1 space group. The structure is one-dimensional and consists of one oxygen molecule and one Pt(NO2)2 ribbon oriented in the (1, 0, 0) direction. In the Pt(NO2)2 ribbon, Pt2+ is bonded to six O2- atoms to form edge-sharing PtO6 octahedra. There are four shorter (2.00 Å) and two longer (2.06 Å) Pt–O bond lengths. N5+ is bonded in a single-bond geometry to one O2- atom. The N–O bond length is 1.29 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one Pt2+ and one N5+ atom. In the second O2- site, O2- is bonded in a water-like geometry to two equivalent Pt2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(N3O2)2 by Materials Project

CuN4(NO2)2 crystallizes in the monoclinic C2/m space group. The structure is zero-dimensional and consists of four nitrous acid molecules and two CuN4 clusters. In each CuN4 cluster, Cu2+ is bonded in a square co-planar geometry to four equivalent N1+ atoms. All Cu–N bond lengths are 1.83 Å. N1+ is bonded in a single-bond geometry to one Cu2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CuH12(N5O4)2 by Materials Project

CuO4N2N2(NH3)4(NO2)2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two ammonia molecules; four ammonia molecules; two hydroxylamine, n-hydroxy- molecules; and one CuO4N2 cluster. In the CuO4N2 cluster, Cu2+ is bonded in a distorted linear geometry to two equivalent O2- atoms. Both Cu–O bond lengths are 2.65 Å. N+0.20+ is bonded in a bent 120 degrees geometry to two O2- atoms. Both N–O bond lengths are 1.25 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one Cu2+ and one N+0.20+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one N+0.20+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn(N3O8)2 by Materials Project

Mn(NO6)2N2(NO2)2 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of four ammonia molecules; four nitrous acid molecules; and one Mn(NO6)2 sheet oriented in the (1, 0, 0) direction. In the Mn(NO6)2 sheet, Mn2+ is bonded in a distorted octahedral geometry to six O2- atoms. There are a spread of Mn–O bond distances ranging from 1.69–2.10 Å. N5+ is bonded in a bent 120 degrees geometry to two O2- atoms. Both N–O bond lengths are 1.26 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one N5+ and one O2- atom. The O–O bond length is 2.39 Å. In the second O2- site, O2- is bonded in a single-bond geometry to one N5+ and one O2- atom. The O–O bond length is 3.02 Å. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Mn2+ and two O2- atoms. There is one shorter (1.29 Å) and one longer (2.38 Å) O–O bond length. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Mn2+ and three O2- atoms. There are one shorter (2.51 Å) and one longer (2.62 Å) O–O bond lengths. In the fifth O2- site, O2- is bonded in a single-bond geometry to one Mn2+ and one O2- atom. The O–O bond length is 3.04 Å. In the sixth O2- site, O2- is bonded in a 6-coordinate geometry to six O2- atoms.

36 MATERIALS SCIENCE↗
NASA NTRS1990

The rate coefficient for the reaction NO2 + NO3 yielding NO + NO2 + O2 from 273 to 313 K

The ratio of rate constants for the reaction NO3 + NO yielding 2 NO2 (k3) and the reaction NO2 + NO3 yielding NO + NO2 + O2 (k4) were determined by measuring of NO and NO2 concentrations of NO and NO2 in an N2O5/NO2/N2 mixture over the temperature range 273-313 K. The measured ratio was found to be expressed by the equation k3/k4 = 387 exp(-1375/T). The results are consistent with those of Hammer et al. (1986).

Cantrell, Chris A.↗
NASA NTRS1994

Peroxy radical measurements with NCAR's chemical amplifier

The present NCAR instrument for HO2/RO2 measurements has been described previously. It is based on the reactions involving HO2, RO2, and HO radicals with CO and NO. Since (HO2) + (RO2) + (HO) is much greater than (HO) for most atmospheres, it is useful as a peroxy radical detector. Operation of the instrument depends on the creation of a chemical chain reaction which is initiated as HO2 and RO2 radicals in ambient air encounter added NO gas; this forms an NO2 molecule and an HO or RO radical: HO2(RO2) + NO yields HO(RO) + NO2. RO radicals react relatively efficiently with O2 to form an HO2 radical, and subsequently an HO-radical, by reaction with NO. CO gas added to the reaction chamber during part of the operating cycle, recycles the HO to HO2; HO + CO (+O2) yields HO2 + CO2. The reaction sequence may form several hundred NO2 molecules per HO2 (RO2) originally present, before chain termination occurs. The added CO is replaced by N2 addition periodically so that the chain reaction is suppressed, and a 'blank' signal resulting from NO2, O3 and possibly other NO2-forming species (non-chain processes) in ambient air is recorded. The difference between the signal with and without CO is proportional to the peroxy radical concentration. The NO2 produced is monitored using a sensitive luminol chemiluminescence detector system. In the NCAR instrument the length of the amplification chain is determined using a stable source of HO2 radicals (H2O2 thermal decomposition); the ratio of the signal seen with CO present to that with N2 present gives the sensitivity of the instrument to HO2 (molecules of NO2 formed/peroxy radical). The instrument is automated to carry out in hourly repeated cycles: (1) chain length determination; (2) NO2 calibration; and (3) linearity check on the response of signals. One minute averages of signals are normally recorded. The sensitivity of the instrument to detect peroxy radicals is in the pptv range. The present instrument has operated continuously (24 hr/day) in the field studies which extended over a period of several weeks. The major advantages of this instrument are as follows: (1) its relative simplicity; (2) low power requirements; and (3) its rapid response to all types of peroxy radicals--HO2, CH3O2 and the higher alkyl and acyl peroxy radicals; however not all RO2 species generate HO2 radicals with perfect efficiency and hence have somewhat lower response/molecule than HO2 radicals.

Cantrell, Christopher↗
NASA NTRS1989

Photo-sensitized ignition of hydrogen/oxygen mixtures for hypersonic flight vehicles

An approach toward improving supersonic ignition and combustion efficiency was investigated under a feasibility program with NASA-Ames. The idea is to selectively irradiate targetted species in the combustion zone. The ensuing photodissociation reactions produce highly reactive radicals which modify the gas phase kinetics. The overall objective of this research was to demonstrate photosensitized ignition of H2/O2 mixtures, and to gain a preliminary understanding of the ignition mechanism, especially as it pertains to the concept of supersonic combustion. To this end, a series of experiments were performed with a model sensitizer, NO2. At subatmospheric pressures and moderate temperatures (above 100 F), mixtures of H2/O2/NO2 are ignitable by a pulsed eximer laser at 308 nm, 115 to 200 mJ. Ignitability was found to be a function of NO2 pressure, temperature, laser energy per pulse, and laser lens focal length (fluence at focal volume). Mixtures could not be ignited in the absence of the sensitizer. While increasing temperature improved sensitized ignition in the lower temperature range, a retarding effect was observed at the highest temperatures. To more thoroughly understand these thermal effects, the UV-Vis and IR spectra of NO2 and H2/O2/NO2 mixtures were studied over the temperature range 70 to 900 F. Initially, increasing temperature shifts the N2O4 in a reversible reaction to 2 NO2 equilibrium toward NO2, favoring photochemical ignition. However, at still higher temperature, NO2 converts to non-absorbing NO + 1/2 O2, thus preventing photosensitized ignition.

Lavid, Moshe↗
DOE OSTI2024

Elucidation of Design Criteria for V‐based Redox Mediators: Structure‐Function Relationships that Dictate Rates of Heterogeneous Electron Transfer

Redox mediators are attractive solutions for addressing the stringent kinetic stipulations required for efficient energy conversion processes. In this work, we compare the electrochemical properties of four vanadium complexes, namely [V(acac) 3 ], [V 6 O 7 (OMe) 12 ], [ n Bu 4 N] 3 [V 6 O 13 (TRIS NO2 ) 2 ], and [ n Bu 4 N] 5 [V 18 O 46 (NO 3 )] in non-aqueous solutions on glassy carbon electrodes. The goal of this study is to investigate the electron transfer kinetics and diffusivity of these compounds under identical experimental conditions to develop an understanding of structure-function relationships that dictate the physicochemical properties of vanadium oxide assemblies. Complex selection was dictated by two criteria – (1) nuclearity of the transition metal complexes (2) distribution of electron density in the native electronic configuration. In conclusion, our analyses establish that electronic communication between metal centers significantly impacts charge transfer kinetics of these vanadium-based compounds.

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

Materials Data on Sn2C6N2O17 by Materials Project

(Sn2(C2O5)3)2N2(NO2)2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional and consists of four ammonia molecules, four nitrous acid molecules, and one Sn2(C2O5)3 framework. In the Sn2(C2O5)3 framework, there are two inequivalent Sn4+ sites. In the first Sn4+ site, Sn4+ is bonded in a pentagonal pyramidal geometry to six O2- atoms. There are a spread of Sn–O bond distances ranging from 2.07–2.25 Å. In the second Sn4+ site, Sn4+ is bonded in a pentagonal pyramidal geometry to six O2- atoms. There are a spread of Sn–O bond distances ranging from 2.33–2.55 Å. There are four inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.24 Å) and one longer (1.30 Å) C–O bond length. In the second C4+ site, C4+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.26 Å) and one longer (1.28 Å) C–O bond length. In the third C4+ site, C4+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.24 Å) and one longer (1.30 Å) C–O bond length. In the fourth C4+ site, C4+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.25 Å) and one longer (1.28 Å) C–O bond length. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Sn4+ and one C4+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.22 Å) and one longer (2.60 Å) O–O bond length. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Sn4+ and one C4+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to one Sn4+ and one C4+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to one Sn4+, one C4+, and one O2- atom. The O–O bond length is 2.92 Å. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Sn4+ and one C4+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Sn4+ and one C4+ atom. In the eighth O2- site, O2- is bonded in a distorted water-like geometry to one Sn4+ and one C4+ atom. In the ninth O2- site, O2- is bonded in a distorted single-bond geometry to one Sn4+ and one C4+ atom. In the tenth O2- site, O2- is bonded in a distorted T-shaped geometry to three O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ReN2(OF2)4 by Materials Project

ReF8(NO2)2 crystallizes in the orthorhombic Pbca space group. The structure is zero-dimensional and consists of sixteen hydroxylamine, n-hydroxy- molecules and eight ReF8 clusters. In each ReF8 cluster, Re6+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of Re–F bond distances ranging from 1.95–1.99 Å. There are eight inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted single-bond geometry to one Re6+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one Re6+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one Re6+ atom. In the fourth F1- site, F1- is bonded in a distorted single-bond geometry to one Re6+ atom. In the fifth F1- site, F1- is bonded in a distorted single-bond geometry to one Re6+ atom. In the sixth F1- site, F1- is bonded in a single-bond geometry to one Re6+ atom. In the seventh F1- site, F1- is bonded in a single-bond geometry to one Re6+ atom. In the eighth F1- site, F1- is bonded in a single-bond geometry to one Re6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CoN5ClO4 by Materials Project

CoN3Cl(NO2)2 crystallizes in the tetragonal I4_1/a space group. The structure is zero-dimensional and consists of sixteen nitrous acid molecules and eight CoN3Cl clusters. In each CoN3Cl cluster, Co2+ is bonded in a 4-coordinate geometry to three N+1.40+ and one Cl1- atom. There is one shorter (1.58 Å) and two longer (1.92 Å) Co–N bond length. The Co–Cl bond length is 2.23 Å. There are two inequivalent N+1.40+ sites. In the first N+1.40+ site, N+1.40+ is bonded in a single-bond geometry to one Co2+ atom. In the second N+1.40+ site, N+1.40+ is bonded in a distorted single-bond geometry to one Co2+ atom. Cl1- is bonded in a single-bond geometry to one Co2+ atom.

36 MATERIALS SCIENCE↗
NASA NTRS1994

Analysis of the physical state of one Arctic polar stratospheric cloud based on observations

During the Arctic Airborne Stratospheric Expedition (AASE) simultaneous measurements of aerosol size distribution and NO(y)(HN03 + NO + NO2 + 2(N205)) were made along ER-2 flight paths. The flow characteristics of the NO(y) instrument allow us to derive the condensed NO(y) amount (assumed to be HN03) present during polar stratospheric cloud (PSC) events. Analysis of the January 24th flight indicates that this condensed HN03 amount does not agree well with the aerosol volume if the observed PSCs are composed of solid nitric acid trihydrate (NAT), as is generally assumed. However, the composition agrees well with that predicted for liquid H2S04/HN03/H20 solution droplets using a new Aerosol Physical Chemistry Model (APCM). The agreement corresponds in detail to variations in temperature and humidity. The weight percentages of H2SO4, HN03, and H2O derived from the measurements all correspond to those predicted for ternary, liquid solutions.

Drdla, K.↗
NASA NTRS2007

Lithium Dinitramide as an Additive in Lithium Power Cells

Lithium dinitramide, LiN(NO2)2 has shown promise as an additive to nonaqueous electrolytes in rechargeable and non-rechargeable lithium-ion-based electrochemical power cells. Such non-aqueous electrolytes consist of lithium salts dissolved in mixtures of organic ethers, esters, carbonates, or acetals. The benefits of adding lithium dinitramide (which is also a lithium salt) include lower irreversible loss of capacity on the first charge/discharge cycle, higher cycle life, lower self-discharge, greater flexibility in selection of electrolyte solvents, and greater charge capacity. The need for a suitable electrolyte additive arises as follows: The metallic lithium in the anode of a lithium-ion-based power cell is so highly reactive that in addition to the desired main electrochemical reaction, it engages in side reactions that cause formation of resistive films and dendrites, which degrade performance as quantified in terms of charge capacity, cycle life, shelf life, first-cycle irreversible capacity loss, specific power, and specific energy. The incidence of side reactions can be reduced through the formation of a solid-electrolyte interface (SEI) a thin film that prevents direct contact between the lithium anode material and the electrolyte. Ideally, an SEI should chemically protect the anode and the electrolyte from each other while exhibiting high conductivity for lithium ions and little or no conductivity for electrons. A suitable additive can act as an SEI promoter. Heretofore, most SEI promotion was thought to derive from organic molecules in electrolyte solutions. In contrast, lithium dinitramide is inorganic. Dinitramide compounds are known as oxidizers in rocket-fuel chemistry and until now, were not known as SEI promoters in battery chemistry. Although the exact reason for the improvement afforded by the addition of lithium dinitramide is not clear, it has been hypothesized that lithium dinitramide competes with other electrolyte constituents to react with lithium on the surface of the anode to form a beneficial SEI. Apparently, nitrides and oxides that result from reduction of lithium dinitramide on the anode produce a thin, robust SEI different from the SEIs formed from organic SEI promoters. The SEI formed from lithium dinitramide is more electronically insulating than is the film formed in the presence of an otherwise identical electrolyte that does not include lithium dinitramide. SEI promotion with lithium dinitramide is useful in batteries with metallic lithium and lithium alloy anodes.

Gorkovenko, Alexander A.↗
NASA NTRS2010

Highlights from 40 Years of Satellite UV Measurements

This year we are celebrating the 40th anniversary of the launch of the Backscatter Ultraviolet (BUV) instrument on NASA's Nimbus-4 satellite. The purpose of this instrument was to demonstrate the capability to measure total column ozone and its vertical distribution from space. The success of this instrument led to about a dozen instruments of this type on various NASA and NOAA satellites. These instruments used a single photomultiplier tube (PMT) that restricted the measurements to 6-12 discrete wavelengths in the 250-380 nm range. With the availability of solid-state detector arrays in the past decade it has been possible to make similar measurements but with hyperspectral (contiguous in wavelength) sampling and enhanced spectral resolution. This has allowed global mapping of several weakly-absorbing trace gases including S0 2, NO2, BrO, HCHO, and CIIOCHO. Since these measurements are affected by clouds and aerosols, a great deal of effort has gone into understanding their effect on ultraviolet radiation- both upwelling and downwelling. The downwelling UV radiation is chemically and biologically active and has both negative (genetic damage, air pollution) and positive (production of vitamin D and OH radical) environmental effects. I will discuss how the interaction of Rayleigh-scattered UV radiation with clouds and aerosols produce a variety of interesting effects that are leading to new methods of remote sensing of their properties. The UV measurements can greatly enhance the information that one derives from more traditional methods that use infrared and visible part of the solar spectrum.

Bhartia, Pawan K.↗
NASA NTRS1963

Planetary Aeronomy: NO2 In the Martian Atmosphere - 2

The transmission curve of the Martian atmosphere derived by Opik is compared with transmission curves of an atmosphere containing various amounts of nitrogen dioxide. It is found that the amount of 6 x l0(exp 18) sq cm column NO2 (or even less) given by Sinton as an upper limit for the Martian NO2 content could adequately explain the phenomenon of the blue haze. This finding made it worthwhile to investigate the effect of the temperature and pressure sensitive equilibrium 2 NO2 reversibly yields N204 upon the total NO2 content and the altitude-number density distributions of NO2 and N204. Computations were carried out for surface temperatures of 273 K, 243 K, 213 K, and 183 K and for three different temperature distributions. The discussion of the results leads to the suggestion of several important new experiments.

Warneck, P.↗
NASA NTRS1990

Reference NO2 calibration system for ground-based intercomparisons during NASA's GTE/CITE 2 mission

An NO2 calibration system, based on a permeation device and a two-stage dynamic dilution system, was designed, constructed, and characterized at the National Bureau of Standards. In this system, calibrant flow entering the second stage was controlled without contacting a metal flow controller, and permeation oven temperature and flow were continuously maintained, even during transport. The system performance and the permeation emission rate were characterized by extensive laboratory tests. This system was capable of accurately delivering known NO2 concentrations in the ppbv and sub-ppbv concentration range with a total uncertainty of approximately 10 percent. The calibration system was placed on board NASA research aircraft at both the Wallops Island and Ames research facilities. There it was employed as the reference standard in NASA's Global Tropospheric Experiment/Chemical Instrumental Test and Evaluation 2 mission in August 1986.

Fried, Alan↗
DOE OSTI2020

Materials Data on Be(N3O7)2 by Materials Project

Be(NO2)3Be(NO2)4(NO2)5(O2)2 crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of two hydrogen peroxide molecules, five nitrous acid molecules, one Be(NO2)3 cluster, and one Be(NO2)4 cluster. In the Be(NO2)3 cluster, Be2+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of Be–O bond distances ranging from 1.54–1.61 Å. There are three inequivalent N+4.33+ sites. In the first N+4.33+ site, N+4.33+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.22 Å) and one longer (1.34 Å) N–O bond length. In the second N+4.33+ site, N+4.33+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.20 Å) and one longer (1.37 Å) N–O bond length. In the third N+4.33+ site, N+4.33+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.21 Å) and one longer (1.31 Å) N–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one N+4.33+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one Be2+ and one N+4.33+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Be2+ and one N+4.33+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one N+4.33+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one N+4.33+ atom. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to one Be2+ and one N+4.33+ atom. In the Be(NO2)4 cluster, Be2+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of Be–O bond distances ranging from 1.57–1.71 Å. There are four inequivalent N+4.33+ sites. In the first N+4.33+ site, N+4.33+ is bonded in a water-like geometry to two O2- atoms. Both N–O bond lengths are 1.29 Å. In the second N+4.33+ site, N+4.33+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.23 Å) and one longer (1.28 Å) N–O bond length. In the third N+4.33+ site, N+4.33+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.21 Å) and one longer (1.35 Å) N–O bond length. In the fourth N+4.33+ site, N+4.33+ is bonded in a 3-coordinate geometry to three O2- atoms. There is two shorter (1.18 Å) and one longer (2.04 Å) N–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one Be2+ and one N+4.33+ atom. In the second O2- site, O2- is bonded in an L-shaped geometry to one Be2+ and one N+4.33+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one N+4.33+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two N+4.33+ atoms. In the fifth O2- site, O2- is bonded in a single-bond geometry to one N+4.33+ atom. In the sixth O2- site, O2- is bonded in an L-shaped geometry to one Be2+ and one N+4.33+ atom. In the seventh O2- site, O2- is bonded in a single-bond geometry to one N+4.33+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Be2+ and one N+4.33+ atom.

36 MATERIALS SCIENCE↗