Particular LEED features on the V2O5 (010) surface indicate that the LEED beam induced transition V2O5 → V12O26 is initiated by domain formation on the surface of the samples. Two different superstructures have been observed, namely V12O26(010)-4 × 1 and V12O26(010)-1 × 2, on non-stoichiometric samples. © 1969.