At the theoretical and computational biophysical chemistry (TCBC) group at DTU Chemistry we're developing and applying computational methods to study large and complex molecular systems. The methods are based on multiscale-modeling approaches aimed at ground- and excited-state molecular dynamics simulations and embedding methods for electronic-structure calculations of spectroscopic properties. Our main focus is on simulating spectroscopic processes in biomolecular systems, such as proteins, cell membranes, and nucleic acids, where the analysis and interpretation of experimental spectroscopic studies can be very challenging. We seek to solve this challenge through computational simulations that can provide the link between the measured spectra and the underlying molecular mechanisms.