TY - JOUR

T1 - Determination of structural parameters for ferrocenecarboxaldehyde using Fourier transform microwave spectroscopy

AU - Subramanian, Ranga

AU - Karunatilaka, Chandana

AU - Schock, Riley O.

AU - Drouin, Brian J.

AU - Cassak, Paul A.

AU - Kukolich, Stephen G.

N1 - Funding Information:
This material is based on the work supported by the National Science Foundation under Grant No. CHE-0304969. This support from the National Science Foundation is gratefully acknowledged. One of the authors (P.A.C.) gratefully acknowledges support from a NASA Arizona Space Grant internship during the course of this project. We thank Oliver Indris, Jennifer Dannemiller, and Kirsten Fields for help in obtaining data on the normal isotopomer.

PY - 2005

Y1 - 2005

N2 - Gas-phase structural parameters for ferrocenecarboxaldehyde have been determined using Fourier transform microwave spectroscopy. Rotational transitions due to a -, b -, and c -type dipole moments were measured. Eighteen rotational constants were determined by fitting the measured transitions of various isotopomers using a rigid rotor Hamiltonian with centrifugal distortion constants. Least-squares fit and Kraitchman analyses have been used to determine the gas-phase structural parameters and the atomic coordinates of the molecule using the rotational constants for various isotopomers. Structural parameters determined from the least-squares fit are the Fe-C bond lengths to the cyclopentadienyl rings, r (Fe-C) =2.047 (4) Å, and the distance between the carbon atoms of the cyclopentadienyl rings, r (C-C) =1.430 (2) Å and r (C1 - C 1′) =1.46 (1) Å of ring carbon and aldehyde carbon atom. Structural parameters were also obtained using density-functional theory calculations, and these were quite helpful in resolving ambiguities in the structural fit analysis, and providing some fixed parameters for the structural analysis. The results of the least squares and the calculations indicate that the carbon atoms of the Cp groups for ferrocenecarboxaldehyde are in an eclipsed conformation in the ground vibrational state.

AB - Gas-phase structural parameters for ferrocenecarboxaldehyde have been determined using Fourier transform microwave spectroscopy. Rotational transitions due to a -, b -, and c -type dipole moments were measured. Eighteen rotational constants were determined by fitting the measured transitions of various isotopomers using a rigid rotor Hamiltonian with centrifugal distortion constants. Least-squares fit and Kraitchman analyses have been used to determine the gas-phase structural parameters and the atomic coordinates of the molecule using the rotational constants for various isotopomers. Structural parameters determined from the least-squares fit are the Fe-C bond lengths to the cyclopentadienyl rings, r (Fe-C) =2.047 (4) Å, and the distance between the carbon atoms of the cyclopentadienyl rings, r (C-C) =1.430 (2) Å and r (C1 - C 1′) =1.46 (1) Å of ring carbon and aldehyde carbon atom. Structural parameters were also obtained using density-functional theory calculations, and these were quite helpful in resolving ambiguities in the structural fit analysis, and providing some fixed parameters for the structural analysis. The results of the least squares and the calculations indicate that the carbon atoms of the Cp groups for ferrocenecarboxaldehyde are in an eclipsed conformation in the ground vibrational state.

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U2 - 10.1063/1.1993593

DO - 10.1063/1.1993593

M3 - Article

AN - SCOPUS:23944508370

VL - 123

JO - Journal of Chemical Physics

JF - Journal of Chemical Physics

SN - 0021-9606

IS - 5

M1 - 054317

ER -