Steven R. Davis

FTIR observation of N≡N stretching fundamentals in hydrogen‐bonded complexes in solid argon

Codeposition of Ar/HF and Ar/N2 samples at 10 K produced the N2‐‐H–F complex as evidenced by a very strong H–F stretching fundamental at 3881.4 cm−1 and a weak new 2332.1 cm−1 band assigned here to the N 3/4 N stretching fundamental based on 14,15N2 and 15N2 substitution. A blue DF shift to 2332. 8 cm−1 indicates a slightly stronger deuterium bond in these floppy complexes relative to the 2327.5 cm−1 Raman fundamental for N2 isolated in solid argon. Similar results were obtained for the weaker HCl and H2O complexes. Three bond stretching modes were observed for the N2‐‐H–F‐‐H–F complex.

Far infrared spectra of (HF)2 and (HF)3 in solid argon

Hydrogen fluoride dimers and trimers have been examined by Fourier transform infrared spectroscopy down to 80 cm-1 in solid argon samples. A weak new 128 cm-1 absorption followed the 189 and 400 cm-1 (HF)2 bands on annealing and is assigned to the hydrogen bond stretching fundamental in solid argon. A similar 124 cm-1 band was associated with 162 and 300 cm-1 (DF)2 bands on annealing and is assigned to the deuterium bond stretching fundamental. This assignment is in agreement with very recent potential surface calculations and deductions (125 ± 5 cm-1) from other gas phase absorption of (HF)2. A sharp new 152·5 cm-1 band was associated with the 446 and 560 cm-1 (HF)3 bands on annealing and is assigned to the antisymmetric hydrogen bond stretching fundamental in cyclic (HF)3 in solid argon. The blue shift to 155·5 cm-1 for cyclic (DF)3 provides evidence of slightly stronger deuterium bonding in the cyclic trimer.

Integrated peer-to-peer applications for advanced emergency response systems. Part II. Technical feasibility

We present a study of the technical feasibility of applying peer-to-peer (P2P) technology to the domain of emergency response. The conceptual feasibility of such an endeavor is described in Integrated Peer-to-Peer Applications for Advanced Emergency Response Systems Part I: Concept of Operations (Bahora, et al.), which argues that current emergency response technologies do not adequately support the dynamic nature of emergency response. To provide support, peer-to-peer networks have been identified as an integrating architecture. We explore the integration of the peer-to-peer architecture, specifically the HyperCast peer-to-peer communications framework, with streaming video communication, GPS-based location awareness, and information access management control to better support emergency response. Upon conclusion of this research, these functionalities were implemented as prototypes.

Infrared spectra and UHF SCF calculations of HF complexes with NO, (NO)2, and NO2

HF complexes with nitric oxide and nitrogen dioxide were prepared in argon matrices and studied using IR spectroscopy and unrestricted Hartree–Fock SCF calculations. The results indicate the formation of three different complexes NO‐‐HF, ONNO‐‐HF, and ONO‐‐HF, in which the hydrogen atom of HF is bound to an oxygen atom of the base in each complex. Perturbations in the N–O stretching base submolecule modes were observed in each complex and all were blue shifted with respect to the free base. From the calculations, the unpaired electron was found to be contained in a π antibonding orbital which is in the plane of the NO–HF and ONO–HF complexes.

FTIR spectra of HF complexes with phenylalkynes in solid argon and nitrogen

Abstract Hydrogen-bonded complexes between phenylacetylene, phenylpropyne and HF have been prepared by reagent condensation in an argon or nitrogen matrix at 12 K. IR spectra of the products provide evidence for two 1:1 (base:HF) complexes in which the HF sub-molecule is bonded to the aromatic ring in one and to the Cue5fcC triple bond in the other. Warming the matrix increases the latter complex at the expense of the former and produces 1:2 complexes with an (HF) 2 subunit bonded to the alkyne subgroup, no 1:2 ring complex being observed. These experiments show that the alkyne bonding site produces a more stable complex than the ring bonding site. Methyl substitution substantially increases the basicity of the acetylene group but not the basicity of the ring.

FTIR spectra of the HF complexes with alkyl cyanides in solid argon

Abstract Ethyl-, i-propyl, and t-butyl cyanide were separately condensed at 9–12K with HF in excess argon producing complexes of the form Rue5f8Cue5fcNue5f8ue5f8HF. Diffusion of HF was accomplished by warming the matrix above 18K which produced 1:2 and 1:3 complexes Rue5f8Cue5fcNue5f8ue5f8(HF)2 and Rue5f8Cue5fcNue5f8ue5f8(HF)3. The HF submolecule stretching frequencies for the 1:1 complexes were very similar, giving absorptions at 3515, 3530 and 3520 cm−1, respectively, while the HF librational modes were observed centered around 650 cm−1. The CN symmetric stretch in the complexes was perturbed to higher energy in each case implying a strengthening of the CN bond, with the C-C3 symmetric stretch in t-butyl cyanide also shifted to higher energy.