Spectroscopy Downloads

• The \mcd directory is again split into \rot and \vib. In \rot the physics and simulation of rotationspectra of diatomic molecules is exemplified. These are MathCad 6 files. In \vibr experimental rotation-vibration spectra of diatomic molecules are analyzed and bond distances determined.
  
• In directory \nmr you find the programs Spin, NMRPlot and ABCFit. In Spin you have to input chemical shifts and spin-spin coupling constants. The spin-Hamiltonian is then generated and diagonalized blockwise. The spinstates together with the transition matrix establish allowed spectral transitions and their intensities which are sorted by frequency and saved. With NMRPlot the spectra can be viewed in the usual format as 'Stick-' or 'Lineplot' and compared to observed spectra. A number of examples, generated by Spin can be rendered with NMRPlot. ABCFit, finally, extracts least-squares fitted chemical shift and coupling constants from observed ABC-(ABX-, AMX-)spectra. You have to provide frequencies and intensities of the measured spectrum. No first order approximations are introduced! ABCfit is similar to the well known program Laocoon by Castellano and Bothner-By. However, it uses intensities in addition to frequencies for the fit. The user can attach weights to these data for the fit: E.g. if the intensities seem to be unreliable, a frequency-only fit can be done. Statistical measures for the quality of the fit are produced which allow to choose the best weights for the combined frequency-intensity fit.
  
• Directory \vibr presents MolVib, an animated simulation program for normal vibrations of polyatomic molecules. VibDoc explains content and format of the input data. Several input files provide examples.
  
• In the same directory the program Ftir demonstrates the steps for obtaining a Fourier-Transfom IR-spectrum and Vibro teaches the analysis of rotation-vibration spectra of diatomic molecules.