Three-dimensional covariance-map imaging is a new technique with the potential for determining structures of gas-phase molecules on timescales fast enough to track chemical changes and record ‘molecular movies’ of chemical reactions.

Due to the energy mismatching between the frontier orbitals of rare-earth metal and ligand atom, the rare-earth metal-phosphorus multiple bonds are very unstable. This Behind introduces our group’s struggling trip to the first rare-earth monometallic phosphinidene complex during the past 10 years.