We present low-energy electron-diffraction (LEED) and photoemission me
asurements of single-crystal surfaces of VO2, made possible using samp
les oriented and characterized in situ. LEED shows that the (100) surf
ace has a (1 x 2) reconstruction, but the (110) and (101) surfaces hav
e diffraction patterns consistent with those expected from termination
of the bulk. The (001) surface is evidently unstable: gentle in situ
heating of our samples causes faceting, while similar heating of cleav
ed single crystals results in irreversible changes in photoemission sp
ectra, which we interpret as surface relaxation of (001) facets. At th
e metal-insulator transition, photoemission spectra of the nearly sixf
old coordinated stable (110) and (101) surfaces change greatly, but sp
ectra of the (001) surface change only slightly. We suggest a coupling
between the electronic and structural instabilities of VO2 may be res
ponsible.