Absorption band strength

FIGURE 14-10 Intrinsic infrared absorption band strengths of some potential greenhouse gases in the atmospheric window (from Ramanathan, 1988a, 1988b). 

Since the absorption band strength decreases about one order of magnitude with each increase in the order of harmonics (i.e., the vibrational quantum... 

Among other new methods, tunable laser absorption spectroscopy using infrared diode lasers offers prospects for improved accuracy and specificity in concentration measurements, when a line-of-sight technique is appropriate. The present paper discusses diode laser techniques as applied to a flat flame burner and to a room temperature absorption cell. The cell experiments are used to determine the absorption band strength which is needed to properly interpret high temperature experiments. Preliminary results are reported for CO concentration measurements in a flame, the fundamental band strength of CO at STP, collision halfwidths of CO under flame conditions, and the temperature dependence of CO and NO collision halfwidths in combustion gases. 

Since the absorption band strength decreases about one order of magnitude with each increase in the order of harmonics (i.e., the vibrational quantum number), the losses at visible and near-IR wavelengths can be appreciably reduced by substituting deuterium or fluorine for hydrogen atoms. Kaino etal have produced low-loss optical fibers at visible wavelengths from deuterated... 

HcI Bq + CalkT) and (A )i = 152.5 HclAi. Often ratios of the MCD parameters, AiIDq, BqIDq, and CqIDq, are normalized to the absorption band strength (Do) when comparing bands of different intensity Dq is given by zeroth moment of the absorption band (y4)o = 326.6 cIDq. 

Kuhn H 1958 Oscillator strength of absorption bands in dye molecules J. Chem. Phys. 29 958-9... 

RRS has also introduced the concept of a Raman excitation profile (REPy for thefth mode) [46, 4lZ, 48, 49, 50 and M]. An REP. is obtained by measuring the resonance Raman scattering strength of thefth mode as a fiinction of the excitation frequency [, 53]. Flow does the scattering intensity for a given (thefth) Raman active vibration vary with excitation frequency within an electronic absorption band In turn, this has led to transfomi theories that try to predict... 

There has been much discussion of the relative contributions of the no-bond and dative structures to the strength of the CT complex. For most CT complexes, even those exhibiting intense CT absorption bands, the dative contribution to the complex stability appears to be minor, and the interaction forces are predominantly the noncovalent ones. However, the readily observed absorption effect is an indication of the CT phenomenon. It should be noted, however, that electronic absorption shifts are possible, even likely, consequences of intermolecular interaetions of any type, and their characterization as CT bands must be based on the nature of the spectrum and the structures of the interaetants. This subject is dealt with in books on CT complexes. ... 

The induced absorption band at 3 eV does not have any corresponding spectral feature in a(co), indicating that it is most probably due to an even parity state. Such a state would not show up in a(co) since the optical transition IAK - mAg is dipole forbidden. We relate the induced absorption bands to transfer of oscillator strength from the allowed 1AS-+1 (absorption band 1) to the forbidden 1 Ak - mAg transition, caused by the symmetry-breaking external electric field. A similar, smaller band is seen in EA at 3.5 eV, which is attributed to the kAg state. The kAg state has a weaker polarizability than the mAg, related to a weaker coupling to the lower 1 Bu state. 

Infrared Hydroxyl Absorption Bands and Hydrogen-bonding Strength (Xv cm ) for Various Sugars and Their Relative Sweetness ... 

The bonds between PAA and Na+, Mg, Ca are purely ionic, but the absorption bands of other cation-PAA interactions - Zn + (1540-1560cm ), Cu (1605cm ) and AP (1600cm )-show evidence of complex formation. The strength and stability of cements parallel the... 

The oscillator strength of the longest wavelength absorption band of BMPC (1.1, [25]) is very similar to those of two previously studied carbocyanines (DOC and DTC) [45] so that we can expect that, for BMPC as well as for EK)C and DTC, the radiative constant (kp) is equal to 2-3x10 s". Combining this value with the fluorescence quantum yield of BMPC in methanol, 4)p= 5.3x10", we can estimate its room-temperarnre fluorescence lifetime to be = 2 ps. 

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