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The X-ray structure of the blue complex, [Cu(L)(N[O.sub.3])][N[O.sub.3]] obtained from the reaction of Cu[(N[O.sub.3]).sub.2]*3[H.sub.2]O with the ligand 1-(ferrocenemethyl)-1,4,7,10-tetraazacyclododecane (L) in acetonitrile showed an unexpected binding of a nitrate anion in that C[u.sup.II] center. The nitrate anion in the C[u.sup.II] center is observed to be surrounded by four N atoms of the 1,4,7,10-tetraazacyclododecane (cyclen) macrocycle and two O atoms from chelating nitrate anion, both Cu-O distances being below the sums of the van de Waals radii.

The interaction of N[O.sub.3] free radical and [N.sub.2][O.sub.5] with decane flame soot is examined in a Knudsen flow reactor at ambient temperature. The inverse concentration dependence of [gamma] below the concentration threshold has revealed a complex reaction mechanism for both N[O.sub.3] and [N.sub.2][O.sub.5].

The initial steps in the gas-phase decomposition of urea and urea nitrate are investigated using electronic structure calculations. The HNO3-catalyzed breakdown of urea HNCO and NH3 is predicted to be the most favorable decomposition pathway for gaseous urea nitrate.

Molecular dynamics simulations for the liquid--vacuum interface of the ionic liquid 1-ethyl-3-methylimidazolium nitrate were performed for both electronically polarizable and nonpolarizable potential energy surfaces. The results revealed that the electronic polarization effect is important for the ionic liquid interface.

Mass spectrometric (MS) methods are used for the analysis of two novel nitramine explosives--hexanitrohexaazaisowurzitane (HNIW) and 4,10-dinitro-2,6,8,12-tetraoxa-4,10-diazaisowurzitane (DTIW). The methods include electrospray (ESI) and aanospheric pressure chemical ionization techniques for liquid chromatography/MS (LC/MS), chemical ionization for direct introduction (DCI), and gas chromatography/MS (CI-GC/MS). It is found that HNIW (438 Da) is detectable using both positive and negative modes of DCI and in the negative mode ESI-MS. Several anions were found to complex with HNIW, e.g., C[F.sub.3]C[O.sub.2.sup.-], [Cl.sup.-], [Br.sup.-], [I.sup.-], N[O.sub.3.sup.-] , and N[O.sub.2.sup.-] . On the other hand, DTIW could only be detected using positive DCI and CI-GC/MS, where an M[H.sup.+] ion (m/z 263) was formed. The fragmentation pathways of the two nitramines were further studied by M[S.sup.2] experiments. Apparently, the main fragmentation pathway of the M[H.sup.+] ion of DTIW involves the loss of nitrous acid. Several anion adducts of HNIW that were studied dissociate to afford neutral HNIW and the added anions. However, [Cl.sup.-] , [Br.sup.-], [I.sup.-], and N[O.sub.2.sup.-] afford a series of fragments that resulted from the dissociation of the isowurzitane structure. For these anions, limit of detection was also found. To understand some of the HNIW fragmentation pathways, DFT calculations were used.

The synthesis of CIC(O)OONO2 is accomplished by photolysis of a mixture of Cl2, NO2 and CO in large excess of O2 at about -70 degree Celcius. The experimental geometry of CIC(O)OONO2 is reproduced reasonably well by B3LYP/6-311+G(2df) calculations, whereas the MP2 approximation predicts the N-O bond considerably too long and the dihedral angle too small.

One, five-Diamino-1 H-tetrazole could easily be protonated by reaction with strong mineral acids, yielding the poorly investigated 1, 5-diaminotetrazolium nitrate and perchlorate. The salts examined show good to reasonable physical properties that include high densities, good thermal stabilities, and distinctive melting points around 100 degree Celsius.

The Raman measurements and density functional theory (DFT) calculations are used to analyze the propensity of pentaerythritol tetranitrate (PETN) to conformational changes. The results revealed that DFT calculations indicated changes in conformation/symmetry is observed through changes in the vibrational spectrum, whereas, the calculated Raman spectra provides support for the conclusion that the S4 symmetry, at ambient conditions, changes to C2 under static high-pressure loading and to C2 or C1 in solution.

The existence of a set of structural criteria for the rational design of molecular receptors which complex NO(sub 3)(super -) anion due to hydrogen bonding interactions. recent research shows that it is possible to chelate three nonconnected urea groups to NO(sub 3)(super -), without any steric effects.

A mechanism for the reaction of the NO3 radical with propene is proposed and discussed on the basis of B3LYP and CASSCF calculations. Comparison of the optimized geometries on a limited number of molecular structures was implemented with calculations at the CASSCF level of theory with the same basis set, building the active space with five electrons in six orbitals.

Ab initio calculations are used to examine the energetics of water-mediated decomposition of gas-phase peroxyacetyl nitrate (PAN) into acetic acid and peroxynitirc acid. The calculation suggests that the formations of PAN hydrate complexes are energetically favorable and stable.

A study was conducted to determine the crystal structure of the ferric Hb-nitrite (Hb(ONO)) complex. The results provided insights into the uncommon O-nitrito binding mode adopted by the nitrite ligand and the physiological interaction between the nitrite anion and Hb.

The metadynamics method was used to determine the lowest free energy reaction path for the decomposition of HOONO in water. No direct path from HOONO to nitrate was observed but a caged radical pair formed along the minimum free energy pathway collapsed to NH[O.sub.3] by radical pair coupling of the N-O bond.

The synthesis and structural characterization of sterically congested nitrate derivatives [U[O.sub.2][(N[O.sub.3]).sub.2]-(Rbtp)] (where Rbtp = 2,6-bis(5,6-dialkyl-1,2,4-triazin-3-yl)pyridine is described. The complex is observed to adopt a particular geometry due the twisting of the bidentate N[O.sub.3] ligands out of the equatorial girdle.

Confocal Raman spectroscopy was used to study the individual Mg[(N[O.sub.3]).sub.2] aerosol particles deposited on a quartz substrate. The hygroscopic and reactive properties of aged mineral and sea salt aerosols are studied.

The article presents a complete description of the structure, stability and the IR spectra of the nitrate anion hydrate clusters, which are formed as a product of microhydration of N[O.sub.3.sup.-]. The surface structures of such complexes are shown to be more stable than the interior structures.

The charge transfer (CT) characteristics and the OH vibrational frequency red shifts in the nitrate (N[O.sub.3.sup.-]) anion-water complexes are studied. The nitrate anion is shown to have no major impact on the CT properties of the complexes.

Ab initio methods are used to study the equilibrium structures, harmonic vibrational frequencies of methyl peroxynitrate and structures of protonated methyl peroxynitrate. Study results present a distinct protonation pattern for methyl peroxynitrate.

Second harmonic generation is used for tracking the interaction of the environmentally important metal cations barium, strontium and cadmium and the nitrate anion fused quartz/water interfaces at pH 7. The second harmonic generation spectrum of surface-bound nitrate has shown a new adsorption band that has gone further into the solar spectrum than nitrate in the aqueous or solid state.

CPMD simulations and thermodynamic integrations are used to study structures of uranyl mono and trinitrate complexes in vacuo and inwater. In the studied series, the modulation of uranyl-ligand distances upon immersion of the complex in water is found to depend on the nature of the ligand and the composition of the complex.

The reaction of Zn(NO3)2.6H2O or Cu(NO3)2.3H2O with the star-shaped ligand 2,4,6-tris(di-2-picolylamino)[1,3,5]-triazine in acetonitrile results in the formation of the mono- pr trinuclear coordination compounds, depending on the metal-to-ligand ratios used during the crystallization process. New theoretical investigations are conducted on nitrate-pi interactions, taking into account the particular position of the anion toward the aromatic ring observed in the crystal structures.

A comprehensive proteomic data set identifying 7792 proteins from a whole mouse brain generated by LC/LC-MS/MS analyses was used to identify nitrated proteins. This analysis resulted in identification of 31 unique nitroyrosine sites within 29 different proteins and more than half of the nitrated proteins that are identified are involved in Parkinson's disease, Alzheimer's disease, or other neurodegenerative disorders.

The release of NO and NO2 from frozen aqueous NaNO3 irradiated at 313 nm is investigated using time-resolved spectroscopic techniques. The kinetic behavior of NO and NO2 signals during on-and-off illumination cycles has confirmed that NO2 is primary photoproduct evolving from the outermost ice layers and has revealed that NO is a secondary species generated deeper in the ice, wherefrom it eventually emerges due to its inertness and larger diffusivity.

NarL is a model response regulator for bacterial two-component signal transduction. Two new cocrystal structures are presented of NarL C-terminal domain DNA binding alone (NarL(super C)) complexed with additional 20mer oligonucleotides representatives of other high-affinity tail-to-tail NarL binding sites found in the upstream promoter regions.

Secondary organic aerosol (SOA) formation from reactions of linear alkenes with NO3 radicals is investigated in an environmental chamber using a thermal desorption particle beam mass spectrometer for particle analysis. A general chemical mechanism is developed to explain the formation of the observed SOA products.

Theoretical predictions of electronic, structural and elastic properties of cubic indium nitride in the zine-blende structure are discussed. The theoretical equilibrium lattice constant is 5.017 A, the band gap is 0.65 eV and the bulk modulus is 145 GPa.

The initial decomposition process of urea nitrate (UN) is studied by using ab initio calculations. A series of the UN reaction paths through one intermediate and two transition states with the evolutions of the initial gaseous species, NH3, HNCO, and HNO3, in that order, are revealed.