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Dust particles covered by icy mantles play a crucial role in the formation of molecules in the Interstellar Medium (ISM). These icy mantles are mainly composed of water but many other chemical species are also contained in these ices. The structure of this ice mantle plays in important role in the capacity to hold other species, promote reactions, and take up energy. It further can be used as a diagnostic tool, since the spectroscopy varies with ice structure. Although amorphous solid water is widely studied and is generally well characterized by different techniques, energetically-induced structural changes, such as ion, electron and photon irradiation, in these materials are less well understood. Selective pumping of specific infrared (IR) vibrational modes can aid in understanding the role of vibrations in restructuring of hydrogen bonding networks. I will present the experimental results on hydrogen bonding changes in ASW induced by mid-IR free-electron laser (FEL) radiation. Upon resonant irradiation, a modification in IR absorption band profile of ASW is observed which is analysed in terms of hydrogen bonding donors and acceptors and the experiments are complimented with Molecular Dynamics simulations to constrain the effect at the molecular level. I will further present work on the formation of complex molecules such as glycine in ASW at low temperatures and without UV light.