Future directions: general discussion

Abstract

Anders Nilsson opened a discussion of the paper by Giulia Galli: When we are comparing the electronic structure of water at ambient conditions with high pressure conditions there can be other changes than only the formation of different species. The basic structure can change quite a bit so that high density becomes more dominating. Can this aspect be part of understanding the electronic structure change?Giulia Galli responded: To really reply to this question we should have simulations (which we do not have yet) as a function of pressure and really have trends as a function of pressure. Hopefully we will have those in the next few months but they are not yet available to us.Anders Nilsson said: There is a shi in the 3a 1 towards the 1b 1 orbital peak when pressure is applied. Could this be the result of forming a disordered bandlike structure in a condensed phase and could there be an increased overlap between orbitals of neighboring molecules with increasing pressure? Giulia Galli replied: Yes indeed, I think this is what we are observing in our simulations. We are now examining other conditions and trying to gure out how this overlap depends on pressure in more detail.Loren Ban commented: Thank you for this nice presentation and the great work, I believe that calculated binding energy spectra of liquids are an important ingredient for further progress in understanding condensed phase electronic structure. These calculations will denitely be very valuable to experimentalists looking at similar systems.You show in Fig. 3 of the paper (https://doi.org/10.1039/d2fd00003b) that the binding energy spectrum of water at HPT is notably different from that at APT both in terms of peak widths and peak positions. For the latter, you nd an overall redshi of the HPT spectra. You also show that ionization energies of 412