摘要:

The interpretation and analysis of perturbed molecular spectra is an interesting and challenging activity. Moreover as the resolution and precision of molecular data improves, a systematic and manageable approach to the problems of interpretation and analysis is mandatory. Such a notion may seem a little radical to many scientists, but let us consider the importance of the determination of a complete anharmonic potential function for even the simplest polyatomic molecules. Without molecular model parameters, recovered from the highest quality spectral data, such determinations are doomed to mediocrity. Consider, also, the simulation of the propagation characteristics of infrared radiation through plantetary atmospheres. Without precise molecular parameters, such simulations, though they may be pretty and interesting, are about as valuable scientifically as 30-year-old MO wave functions for a pentatomic molecule. It is not only necessary to be able to recover precise molecular model parameters from the highest resolution molecular spectra, it is also necessary to be able to calculate molecular rotation-vibration energy levels with extremely high precision (on the order of 1% of the Doppler width of a typical transition). Such precision is particularly important in the prediction of long path atmospheric transmission properties for monochromatic radiation.

ISSN:0570-4928    

DOI:10.1080/05704928708060443

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Part I of this review [1] presented an overview of the study of perturbed spectra, the formal structure of vibration-rotation energy states, the systematic determination of symmetry allowed interactions, the representation and calculation of perturbed energies, and the inverse eigenvalue problem. In this concluding part we first consider perturbation effects on transition frequency and intensity in light of the formalism of Part I. Following this we develop a formalism for fitting perturbed spectra and carry out several example cases. Following these examples, we present a real case study of a perturbed system of vibration-rotation bands that illustrates a series of nearly insuperable problems in analysis. In the process of describing the approach to analysis, much of what was presented in Part I will be made concrete. In addition, the case study should give light to a number of areas only mentioned in passing in Part I.

ISSN:0570-4928    

DOI:10.1080/05704928708060444

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Near-infrared (near-IR, NIR) spectroscopy has been a regularly used technique in agriculture and textile manufacturing for some years [1–61. However, the pharmaceutical industry has been slow to accept near-JR as an everyday analytical process. One reason may be its lack of primary absorption bands. All NIR absorbances are overtones of bands originating in the midrange infrared spectrum (4000–17000 nm). In addition, most of the near-JR spectrum of organic compounds (800–3500 nm) is attributable to combinations of the aforementioned over-tones. These “shortcomings” are more than compensated for by the attributes of near-IR instrumentation. Several excellent reviews have recently been published on the theory and instrumentation involved in near-IR reflectance analysis (NIRA) [7–10].

ISSN:0570-4928    

DOI:10.1080/05704928708060445

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

This is a scanned image of the original Editorial Board page(s) for this issue.

ISSN:0570-4928    

DOI:10.1080/05704928708060442

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor