A molecule below refers everywhere to an electron-molecule: a bare nucleus surrounded by however many electrons are needed to make it electrically neutral.
A muon-molecule (μolecule) below refers to a bare nucleus surrounded by however many muons are needed to make it electrically neutral. Since muons are very short lived (microseconds) there are no multi-muonic μolecules as there are certainly multi-electonic molecules without which the Earth and life could never have existed.
Nuclei are composed of protons and neutrons counting the number of each for the isotope number definition. The number of protons identifies the element on the Period Table of the Elements. The first four isotopes are
When a negatively charged muon (μ-) enters a chamber of molecular hydrogen gas including its isotopes of deuterium and tritium, the greater mass of the muon (200x electron mass) offers a stronger binding to either the deuteron (d+) in deuterium or the triton (t+) in tritium than offered by electrons. If thereupon the muon enters the vast empty space inside either of the the de or te atoms, and if the muon strikes close enough to the nucleus, the muon can form a muon-atomic bound state with either the deuteron -- forming a dμ -- or triton -- forming a tμ -- setting the originally electronic-atom electron free to go into the background.
The muon thus kicks sand in the electron's "face" stealing his deuteron or triton "girl".
The same theft occurs when a dμ atom approaches an electronic tritium atom te. The greater mass of the triton over the deuteron leads to a tighter binding of muons to tritons than of muons to deuterons. Therefore, the muon transfers from the dμ atom over to the triton forming a tμ atom since the tighter binding is a lower energy state. The deuteron is then released to undergo further background collisions.
The now muon-infested chamber therefore ultimately has numbers of dμ and tμ atoms undergoing collisions with electronic molecules of deuterium and tritium, where all the lower energy bound states will be filled in order to minimize the energy in the chamber.