Mid-infrared photo-induced force microscopy (IR-PiFM/PiF-IR) -- Answers to some questions

Mid-infrared photo-induced force microscopy (IR-PiFM/PiF-IR) enables high-resolution chemical imaging of surfaces with lateral resolution less than 5 nm. Here are some answers to questions about the physical background, practical handling and potential applications of PiF-IR including its use in the context of studying antimicrobial interaction. Such questions had been addressed to me during the Faraday Discussions on Vibrations at Interfaces which took place in April 2026 in Manchester/UK. The discussion was part of the theme “What is the question, what is the technique?” in the context of which I presented our recent work [James et al., Faraday Discussions, 2026, doi: 10.1039/d6fd00003g]. A modified version of this manuscript will be published in the themed collection “Vibrations at Interfaces” in Faraday Discussions.