The geometries and insertion reactions of germylene H2GeNaF with R—H (R=F, OH, NH2, CH3) have been investigated at the B3LYP/6‐311+G level of theory. The potential barriers of the four reactions are ∼52, 120, 184, and 257 kJ/mol, including the ZPVE corrections, respectively. Here, all the mechanisms of the four reactions are identical to each other; i.e., an intermediate has been located during the insertion reaction. The intermediate could dissociate into substituted germylane and NaF with the barrier corresponding to the dissociation energy. Correspondingly, the reaction energies for the four reactions are −43, −4, 21, and 51 kJ/mol, respectively. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 [ABSTRACT FROM AUTHOR]