Interpretability meets accuracy in computational spectroscopy: The virtual multifrequency spectrometer

The virtual multifrequency spectrometer (VMS) integrates state-of-the-art computational implementations of different spectroscopies with a powerful graphical user interface, which offers an invaluable aid in preorganizing and displaying the computed spectroscopic information. This chapter provides an overview of the VMS software, thus focusing on its peculiarities and unique features. It presents a short introduction of the theoretical background for the selected spectroscopies and of the corresponding quantum chemical requirements. The chapter also presents the current status of VMS in some detail with specific reference to rotational, vibrational, vibronic, and magnetic spectroscopy. To address the great potentialities of the VMS software, various case studies have been selected. The choice has been made in order not only to point out the ability of VMS in dealing with different spectroscopic techniques and thus providing an exhaustive characterization but also to demonstrate the scientific impact of VMS in the field.