This talk describes how DFT calculations have been used to understand results from muon experiments. The talk describes the status of computer simulations applied to MuSR experiments and which are the main problems and challenges that need to be addressed. Essentially, I presented a summary of the main ideas behind DFT and how this technique has been used in combination with muon experiments. This talk was divided in four parts.
The first briefly discuss the key concepts of DFT, which are the main approximations used in this theory and why some of these approximations are relevant to muon experiments -. Also, at the end of this first section, I presented some of the current codes that implement DFT.
In the second part of the talk, I discussed how DFT has been used to study muonated molecular systems, such as Carbenes and muonated Bencene.
In the third part, I discussed some recent results that used DFT to study diamagnetic and paramagnetic states of muons in solid crystalline systems: The example discussed is connected to fluorides.
Finally, in the last part I very briefly mentioned the work that we are doing at STFC on improving some of the current DFT approximations used for muon systems. In particular, I talked about DFT techniques that can be used to estimate the zero point energy contribution and the temperature dependence of the muonium hyperfine coupling constant, and I also mentioned some DFT-based techniques that can help determine the location of the muon stopping sites.