PMID- 18754607
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20090115
LR  - 20080922
IS  - 1520-5215 (Electronic)
IS  - 1089-5639 (Linking)
VI  - 112
IP  - 38
DP  - 2008 Sep 25
TI  - Accurate determination of the structure of cyclooctatetraene by femtosecond 
      rotational coherence spectroscopy and ab initio calculations.
PG  - 9134-43
LID - 10.1021/jp803523y [doi]
AB  - We combine femtosecond time-resolved rotational coherence spectroscopy with 
      high-level ab initio theory to obtain accurate structural information for the 
      nonpolar antiaromatic molecule 1,3,5,7-cyclooctatetraene (C8H8, COT) and its 
      perdeuterated isotopomer COT-d8 (C8D8). We measure the rotational B0 and 
      centrifugal distortion constants D(J), D(JK) of the v = 0 states of COT and 
      COT-d8 to high accuracy, e.g. B0 (COT) = 2710.329(56) MHz, as well as B(v) for 
      the v = 1 states nu6, nu11, nu17, nu22, and nu41/nu42 of COT. The experimental 
      rotational constants are compared to those obtained from calculations at the 
      coupled-cluster with single, double, and perturbative triples [CCSD(T)] level. 
      The latter also take into account vibrational averaging effects of the ground and 
      vibrationally excited states. Combining the experimental and calculated 
      rotational constants with the calculated equilibrium bond lengths and angles 
      allows us to determine accurate equilibrium structure parameters, e.g., r(e) 
      (C-C) = 147.0 +/- 0.05 pm, r(e) (C=C) = 133.7 +/- 0.1 pm, and r(e) (C-H) = 107.9 
      +/- 0.1 pm. The equilibrium C-C and C=C bond lengths of COT are compared to those 
      of 1,3-butadiene. The expected effect of decreased pi-electron delocalization due 
      to the twisting of adjacent C=C double bonds in COT relative to butadiene is 
      observed for the C-C bonds but not for the C=C bonds.
FAU - Kummli, Dominique S
AU  - Kummli DS
AD  - Departement fur Chemie and Biochemie, Universitat Bern, Freiestrasse 3, CH-3000 
      Bern 9, Switzerland.
FAU - Lobsiger, Simon
AU  - Lobsiger S
FAU - Frey, Hans-Martin
AU  - Frey HM
FAU - Leutwyler, Samuel
AU  - Leutwyler S
FAU - Stanton, John F
AU  - Stanton JF
LA  - eng
PT  - Journal Article
DEP - 20080828
PL  - United States
TA  - J Phys Chem A
JT  - The journal of physical chemistry. A
JID - 9890903
EDAT- 2008/08/30 09:00
MHDA- 2008/08/30 09:01
CRDT- 2008/08/30 09:00
PHST- 2008/08/30 09:00 [pubmed]
PHST- 2008/08/30 09:01 [medline]
PHST- 2008/08/30 09:00 [entrez]
AID - 10.1021/jp803523y [doi]
PST - ppublish
SO  - J Phys Chem A. 2008 Sep 25;112(38):9134-43. doi: 10.1021/jp803523y. Epub 2008 Aug 
      28.