### Abstract

Pulsed-beam Fourier transform microwave spectroscopy was used to measure a and b dipole transitions for the N_{2}O-H^{35}Cl, N _{2}O-H^{37}Cl, N_{2}O-D^{35}Cl, and ^{15}NNO-H^{35}Cl van der Waals complexes. The observed transition frequencies were fit to determine the spectroscopic constants A-D_{K}, B, C, D_{j}, D_{JK}, eQq_{aa}(Cl), and eQq_{bb}(Cl). The structure of the complex appears to be a planar asymmetric top with a centers-of-mass separation R_{c.m.}- ≈ 3.51 Å. The angle θ between R_{c.m.} and the HCl axis is approximately 110°. The angle φ between the N_{2}O axis and R_{c.m.} is approximately 77°. The structure was fit using a weighted least squares fit to B and C isotopic rotational constants with R _{c.m.} θ, and φ as the adjustable parameters, and this procedure yielded three local minima with standard deviations less than 5 MHz. Principal axis coordinates for the Cl, H, and terminal N atoms in the complex were determined with single isotopic Kraitchman analysis to aid in the selection of the "best" structure. In a second structural analysis R _{c.m.} θ, and φ values were determined from the spectroscopic constants B, C, and eQq_{aa}(Cl). The "best fit" structure parameters for N_{2}O-HCl are R_{c.m.} = 3.512(2) Å, θ = 110(9)°, and θ = 77(2)°. Ab initioa calculations of N_{2}O-HCl structures using GAUSSIAN86 with MP2 yielded three energetically stable equilibrium conformations. One of the bound structures is very similar to the present experimental vibrationally averaged structure.

Original language | English (US) |
---|---|

Pages (from-to) | 899-907 |

Number of pages | 9 |

Journal | The Journal of Chemical Physics |

Volume | 94 |

Issue number | 2 |

State | Published - 1991 |

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### ASJC Scopus subject areas

- Atomic and Molecular Physics, and Optics

### Cite this

*The Journal of Chemical Physics*,

*94*(2), 899-907.

**Microwave measurements and theoretical calculations on the structures of NNO-HCl complexes.** / Pauley, D. J.; Roehrig, M. A.; Adamowicz, Ludwik; Shea, J. C.; Haubrich, S. T.; Kukolich, Stephen G.

Research output: Contribution to journal › Article

*The Journal of Chemical Physics*, vol. 94, no. 2, pp. 899-907.

}

TY - JOUR

T1 - Microwave measurements and theoretical calculations on the structures of NNO-HCl complexes

AU - Pauley, D. J.

AU - Roehrig, M. A.

AU - Adamowicz, Ludwik

AU - Shea, J. C.

AU - Haubrich, S. T.

AU - Kukolich, Stephen G

PY - 1991

Y1 - 1991

N2 - Pulsed-beam Fourier transform microwave spectroscopy was used to measure a and b dipole transitions for the N2O-H35Cl, N 2O-H37Cl, N2O-D35Cl, and 15NNO-H35Cl van der Waals complexes. The observed transition frequencies were fit to determine the spectroscopic constants A-DK, B, C, Dj, DJK, eQqaa(Cl), and eQqbb(Cl). The structure of the complex appears to be a planar asymmetric top with a centers-of-mass separation Rc.m.- ≈ 3.51 Å. The angle θ between Rc.m. and the HCl axis is approximately 110°. The angle φ between the N2O axis and Rc.m. is approximately 77°. The structure was fit using a weighted least squares fit to B and C isotopic rotational constants with R c.m. θ, and φ as the adjustable parameters, and this procedure yielded three local minima with standard deviations less than 5 MHz. Principal axis coordinates for the Cl, H, and terminal N atoms in the complex were determined with single isotopic Kraitchman analysis to aid in the selection of the "best" structure. In a second structural analysis R c.m. θ, and φ values were determined from the spectroscopic constants B, C, and eQqaa(Cl). The "best fit" structure parameters for N2O-HCl are Rc.m. = 3.512(2) Å, θ = 110(9)°, and θ = 77(2)°. Ab initioa calculations of N2O-HCl structures using GAUSSIAN86 with MP2 yielded three energetically stable equilibrium conformations. One of the bound structures is very similar to the present experimental vibrationally averaged structure.

AB - Pulsed-beam Fourier transform microwave spectroscopy was used to measure a and b dipole transitions for the N2O-H35Cl, N 2O-H37Cl, N2O-D35Cl, and 15NNO-H35Cl van der Waals complexes. The observed transition frequencies were fit to determine the spectroscopic constants A-DK, B, C, Dj, DJK, eQqaa(Cl), and eQqbb(Cl). The structure of the complex appears to be a planar asymmetric top with a centers-of-mass separation Rc.m.- ≈ 3.51 Å. The angle θ between Rc.m. and the HCl axis is approximately 110°. The angle φ between the N2O axis and Rc.m. is approximately 77°. The structure was fit using a weighted least squares fit to B and C isotopic rotational constants with R c.m. θ, and φ as the adjustable parameters, and this procedure yielded three local minima with standard deviations less than 5 MHz. Principal axis coordinates for the Cl, H, and terminal N atoms in the complex were determined with single isotopic Kraitchman analysis to aid in the selection of the "best" structure. In a second structural analysis R c.m. θ, and φ values were determined from the spectroscopic constants B, C, and eQqaa(Cl). The "best fit" structure parameters for N2O-HCl are Rc.m. = 3.512(2) Å, θ = 110(9)°, and θ = 77(2)°. Ab initioa calculations of N2O-HCl structures using GAUSSIAN86 with MP2 yielded three energetically stable equilibrium conformations. One of the bound structures is very similar to the present experimental vibrationally averaged structure.

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M3 - Article

AN - SCOPUS:0037576908

VL - 94

SP - 899

EP - 907

JO - Journal of Chemical Physics

JF - Journal of Chemical Physics

SN - 0021-9606

IS - 2

ER -