Infrared Spectroscopic and Theoretical Investigations of Group 13 Oxyfluorides OMF and OMF (M=B, Al, Ga, In).

Group 13 oxyfluorides OMF were produced by the reactions of laser-ablated group 13 atoms M (M=B, Al, Ga and In) with OF and isolated in excess neon or argon matrices at 5 K. These molecules were characterized by matrix-isolation infrared spectroscopy and isotopic substitution experiments in conjunction with quantum-chemical calculations. The calculations indicate that the OMF molecules have a B ground state with C symmetry.

Observation and Characterization of the Hg-O Diatomic Molecule: A Matrix-Isolation and Quantum-Chemical Investigation.

Mercuric oxide is a well-known and stable solid, but the diatomic molecule Hg-O is very fragile and does not survive detection in the gas phase. However, laser ablation of Hg atoms from a dental amalgam alloy target into argon or neon containing about 0.3 % of O or of O during their condensation into a cryogenic matrix at 4 K allows the formation of O atoms which react on annealing to make ozone and new IR absorptions in solid argon at 521.

Investigation of Molecular Iridium Fluorides IrF (n=1-6): A Combined Matrix-Isolation and Quantum-Chemical Study.

The photo-initiated defluorination of iridium hexafluoride (IrF ) was investigated in neon and argon matrices at 6 K, and their photoproducts are characterized by IR and UV-vis spectroscopies as well as quantum-chemical calculations. The primary photoproducts obtained after irradiation with λ=365 nm are iridium pentafluoride (IrF ) and iridium trifluoride (IrF ), while longer irradiation of the same matrix with λ=278 nm produced iridium tetrafluoride (IrF ) and iridium difluoride (IrF ) by Ir-F bond cleavage or F elimination. In addition, IrF can be reversed to IrF by adding a F atom when exposed to blue-light (λ=470 nm) irradiation.

(Noble Gas) -NC Molecular Ions in Noble Gas Matrices: Matrix Infrared Spectra and Electronic Structure Calculations.

An investigation of pulsed-laser-ablated Zn, Cd and Hg metal atom reactions with HCN under excess argon during co-deposition with laser-ablated Hg atoms from a dental amalgam target also provided Hg emissions capable of photoionization of the CN photo-dissociation product. A new band at 1933.4 cm in the region of the CN and CN gas-phase fundamental absorptions that appeared upon annealing the matrix to 20 K after sample deposition, and disappeared upon UV photolysis is assigned to (Ar) CN , our key finding.

Cyanides, Isocyanides, and Hydrides of Zn, Cd and Hg from Metal Atom and HCN Reactions: Matrix Infrared Spectra and Electronic Structure Calculations.

Zinc and cadmium atoms from laser ablation of the metals and mercury atoms ablated from a dental amalgam target react with HCN in excess argon during deposition at 5 K to form the MCN and MNC molecules and CN radicals. UV irradiation decreases the higher energy ZnNC isomer in favor of the lower energy ZnCN product. Cadmium and mercury atoms produce analogous MCN primary molecules.

The phenylselenyl radical and its reaction with molecular oxygen.

The current study focuses on the generation, identification, and characterization of the phenylselenyl radical using the matrix isolation technique in combination with density functional theory (B3LYP/cc-pVTZ) computations. The hitherto unknown phenylselenyl peroxy radical was synthesized by co-condensation of the phenylselenyl radical with molecular ground state triplet oxygen from the gas phase and subsequent trapping in argon matrices at 10 K. The experimental IR spectra including O isotopically labelled materials compare well with the data obtained from B3LYP/cc-pVTZ computations.

Formation of Hydroxylamine in Low-Temperature Interstellar Model Ices.

We irradiated binary ice mixtures of ammonia (NH) and oxygen (O) ices at astrophysically relevant temperatures of 5.5 K with energetic electrons to mimic the energy transfer process that occurs in the track of galactic cosmic rays. By monitoring the newly formed molecules online and in situ utilizing Fourier transform infrared spectroscopy complemented by temperature-programmed desorption studies with single-photon photoionization reflectron time-of-flight mass spectrometry, the synthesis of hydroxylamine (NHOH), water (HO), hydrogen peroxide (HO), nitrosyl hydride (HNO), and a series of nitrogen oxides (NO, NO, NO, NO, NO) was evident.

Is Magnetic Bistability of Carbenes a General Phenomenon? Isolation of Simple Aryl(trifluoromethyl)carbenes in Both Their Singlet and Triplet States.

p-Tolyl(trifluoromethyl)carbene and the related fluorenyl(trifluoromethyl)carbene were synthesized in solid argon and characterized by IR, UV-vis, and electron paramagnetic resonance spectroscopy as well as by quantum mechanical calculations. The carbenes can be generated in both their triplet and singlet states, and both states coexist under the conditions of matrix isolation. According to our calculations, the singlet and triplet states of these carbenes are energetically nearly degenerate in the gas phase.

On the Formation of N3 H3 Isomers in Irradiated Ammonia Bearing Ices: Triazene (H2 NNNH) or Triimide (HNHNNH).

The remarkable versatility of triazenes in synthesis, polymer chemistry and pharmacology has led to numerous experimental and theoretical studies. Surprisingly, only very little is known about the most fundamental triazene: the parent molecule with the chemical formula N3 H3 . Here we observe molecular, isolated N3 H3 in the gas phase after it sublimes from energetically processed ammonia and nitrogen films.

Electron Paramagnetic Resonance Spectroscopic Study on Nonequilibrium Reaction Pathways in the Photolysis of Solid Nitromethane (CH3NO2) and D3-Nitromethane (CD3NO2).

Thin films of nitromethane (CH3NO2) along with its isotopically labeled counterpart D3-nitromethane (CD3NO2) were photolyzed at discrete wavelength between 266 nm (4.7 eV) and 121 nm (10.2 eV) to explore the underlying mechanisms involved in the decomposition of model compounds of energetic materials in the condensed phase at 5 K.