  We investigate the electronic and structural changes at the nanoscale in
vanadium dioxide (VO2) in the vicinity of its thermally driven phase
transition. Both electronic and structural changes exhibit phase coexistence
leading to percolation. In addition, we observe a dichotomy between the local
electronic and structural transitions. Nanoscale x-ray diffraction reveals
local, non-monotonic switching of the lattice structure, a phenomenon that is
not seen in the electronic insulator-to-metal transition mapped by near-field
infrared microscopy.
