### Abstract

An isolated complex of C _{2}H _{4} and ICF _{3} has been generated in the gas phase and studied by chirped-pulse, Fourier transform microwave (CP-FTMW) spectroscopy. Ab initio calculations at the CCSD(T)(F12)/VTZ level support the experimental work and further establish the dissociation energy, D _{e}, and dipole moment, μ, of the complex. Rotational constants, B _{0} and C _{0}, the centrifugal distortion constant, Δ _{J}, nuclear quadrupole coupling constants, χ _{aa} (I) and (χ _{bb}(I)-χ _{cc}(I)) and the nuclear spin-rotation coupling constant C _{bb}(I) of the complex are determined from the experimental data. The iodine atom interacts with π-electrons on C _{2}H _{4} resulting in the formation of a linear (∠(CI⋯)) halogen bond (where indicates the centre of the CC bond) and a complex of C _{s} symmetry. The measured rotational constants allow the length of the halogen bond to be determined as 3.434(2) Å in the r _{0} geometry. The complex is formally an asymmetric top but with a very low barrier to internal rotation of C _{2}H _{4} about the C _{3} axis defined by the CF _{3}I sub-unit. Adopting an approach also used in a recent study of H _{2}O⋯ICF _{3}, other transitions are assigned using the Hamiltonian of a symmetric top molecule.

Original language | English |
---|---|

Pages (from-to) | 47-53 |

Number of pages | 7 |

Journal | Journal of Molecular Spectroscopy |

Volume | 280 |

Issue number | 1 |

DOIs | |

Publication status | Published - Oct 1 2012 |

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### All Science Journal Classification (ASJC) codes

- Atomic and Molecular Physics, and Optics
- Spectroscopy
- Physical and Theoretical Chemistry

### Cite this

_{2}H

_{4}⋯ICF

_{3}identified by broadband rotational spectroscopy.

*Journal of Molecular Spectroscopy*,

*280*(1), 47-53. https://doi.org/10.1016/j.jms.2012.06.002

**The halogen bond between ethene and a simple perfluoroiodoalkane : C _{2}H _{4}⋯ICF _{3} identified by broadband rotational spectroscopy.** / Stephens, Susanna L.; Mizukami, Wataru; Tew, David P.; Walker, Nicholas R.; Legon, Anthony C.

Research output: Contribution to journal › Article

_{2}H

_{4}⋯ICF

_{3}identified by broadband rotational spectroscopy',

*Journal of Molecular Spectroscopy*, vol. 280, no. 1, pp. 47-53. https://doi.org/10.1016/j.jms.2012.06.002

_{2}H

_{4}⋯ICF

_{3}identified by broadband rotational spectroscopy. Journal of Molecular Spectroscopy. 2012 Oct 1;280(1):47-53. https://doi.org/10.1016/j.jms.2012.06.002

}

TY - JOUR

T1 - The halogen bond between ethene and a simple perfluoroiodoalkane

T2 - C 2H 4⋯ICF 3 identified by broadband rotational spectroscopy

AU - Stephens, Susanna L.

AU - Mizukami, Wataru

AU - Tew, David P.

AU - Walker, Nicholas R.

AU - Legon, Anthony C.

PY - 2012/10/1

Y1 - 2012/10/1

N2 - An isolated complex of C 2H 4 and ICF 3 has been generated in the gas phase and studied by chirped-pulse, Fourier transform microwave (CP-FTMW) spectroscopy. Ab initio calculations at the CCSD(T)(F12)/VTZ level support the experimental work and further establish the dissociation energy, D e, and dipole moment, μ, of the complex. Rotational constants, B 0 and C 0, the centrifugal distortion constant, Δ J, nuclear quadrupole coupling constants, χ aa (I) and (χ bb(I)-χ cc(I)) and the nuclear spin-rotation coupling constant C bb(I) of the complex are determined from the experimental data. The iodine atom interacts with π-electrons on C 2H 4 resulting in the formation of a linear (∠(CI⋯)) halogen bond (where indicates the centre of the CC bond) and a complex of C s symmetry. The measured rotational constants allow the length of the halogen bond to be determined as 3.434(2) Å in the r 0 geometry. The complex is formally an asymmetric top but with a very low barrier to internal rotation of C 2H 4 about the C 3 axis defined by the CF 3I sub-unit. Adopting an approach also used in a recent study of H 2O⋯ICF 3, other transitions are assigned using the Hamiltonian of a symmetric top molecule.

AB - An isolated complex of C 2H 4 and ICF 3 has been generated in the gas phase and studied by chirped-pulse, Fourier transform microwave (CP-FTMW) spectroscopy. Ab initio calculations at the CCSD(T)(F12)/VTZ level support the experimental work and further establish the dissociation energy, D e, and dipole moment, μ, of the complex. Rotational constants, B 0 and C 0, the centrifugal distortion constant, Δ J, nuclear quadrupole coupling constants, χ aa (I) and (χ bb(I)-χ cc(I)) and the nuclear spin-rotation coupling constant C bb(I) of the complex are determined from the experimental data. The iodine atom interacts with π-electrons on C 2H 4 resulting in the formation of a linear (∠(CI⋯)) halogen bond (where indicates the centre of the CC bond) and a complex of C s symmetry. The measured rotational constants allow the length of the halogen bond to be determined as 3.434(2) Å in the r 0 geometry. The complex is formally an asymmetric top but with a very low barrier to internal rotation of C 2H 4 about the C 3 axis defined by the CF 3I sub-unit. Adopting an approach also used in a recent study of H 2O⋯ICF 3, other transitions are assigned using the Hamiltonian of a symmetric top molecule.

UR - http://www.scopus.com/inward/record.url?scp=84867679404&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84867679404&partnerID=8YFLogxK

U2 - 10.1016/j.jms.2012.06.002

DO - 10.1016/j.jms.2012.06.002

M3 - Article

AN - SCOPUS:84867679404

VL - 280

SP - 47

EP - 53

JO - Journal of Molecular Spectroscopy

JF - Journal of Molecular Spectroscopy

SN - 0022-2852

IS - 1

ER -