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This article was published online on 9 April 2010 but the captions to figures 4 and 5 must be corrected as follows. This corrigendum also applies to the print version published as article 064028 in this issue. Figure 4. B(E2) values, relative to the B(E2; 21+ → 01+) value, observed for 112Cd. The uncertainties for the last digit are listed in parentheses. Dashed transitions indicate an unobserved transition. Underlined numbers indicate a B(E2) value relative to the strongest transition (defined as 100 units) from the level. (The upper limit for the E2, 2121 → 1312 transition is dictated by the δ(E2/M1) value for the 2121 → 1312 transition.) Figure 5. Systematics of B(E2) values for the even–even Cd isotopes 110–116Cd. Transitions are labelled with their B(E2) values in W.u. with 1σ uncertainties on the last digit in the parentheses; the listing of two numbers reflects asymmetric uncertainties with +1σ and −1σ, respectively. Values without uncertainties are relative B(E2) values, or upper limits. Dashed arrows indicate unobserved transitions where upper limits have been established. Of particular note are the greatly disparate values in 114Cd between results of Coulomb excitation and lifetime measurements for some levels, the most serious of which occurs for the 1842 keV 2+ level; the values obtained from Coulomb excitation are listed above the transitions and are up to a factor of ∼35 greater than those derived from the most stringent lifetime limits. Figures 4 and 5 with their corrected captions are presented in the associated PDF file.

The spectrum of 1,1,1,2-tetrafluoroethane gas has been examined in the far infrared (50–420 cm—1). Bands were observed at 120, 225, 350, and 409 cm—1. The contour of the strong band at 120 cm—1 is consistent with that to be expected for the torsional oscillation. This frequency would correspond to a triple cosine barrier of 4.2 kcal/mole.

Articles you may be interested inThe effect of hydrogen bonding on torsional dynamics: A combined far-infrared jet and matrix isolation study of methanol dimer Considerable discrepancies are frequently observed between the values of torsional barriers detennined by microwave splitting and those obtained from far-infrared transitions, if the usual rigid-top--rigid-frame model is employed. If a nonrigid model which includes first-order coupling with the internal vibrations is used, the requirement of consistency between the microwave and infrared data permits barrier Fourier coefficients Va and V6 to be evaluated without any prior choice of a value of Ired, the reduced moment of the top. This has hitherto been the principal source of uncertainty in the determination of barrier parameters. The torsional parameters F, I red, S, Cl, and f3 are also independently evaluated; from these I a is detennined. Comparison of the "self-consistent" and "a priori" values of parameters such as Ia indicates the extent of interaction with other normal vibrations. The limitation of the treatment involved by the neglect of secondorder vibrational interaction terms, such as centrifugal distortion, can be assessed in cases where microwave data from torsionally excited states is available. The method is applied to CHaCHO, CDaCHO, and CHaCH= CH2, for which accurate far-infrared spectra have been newly determined.