ANSWER:
MOLECULAR IONS:
“When a molecule loses or gains an electron, it forms a molecular ion.”
Formation of Molecular Ions:
Molecular ions can be generated by passing high-energy electron beams or α-particles or X–rays through a substance present in gaseous form.
Examples: CH4+, N2+, CO+ etc.
(Ref. An Insight Into Objective Chemsitry-11, Ch-01, Q. No. 12)