Structures of the4×1and1×2reconstructions ofSnO2(110)

Scanning tunneling microscopy (STM) and noncontact atomic-force microscopy (AFM) have been used to investigate the $4\times 1$ and $1\times 2$ reconstructions of ${\mathrm{SnO}}_2\mathrm{}\left(110\right)\mathrm{}.$ These terminations were prepared by sequential annealing in UHV at temperatures of 900 and 1075 K, respectively. Two coexisting $4\times 1$ structures are observed with STM, one of which is consistent with previously reported STM images, the other appearing to arise from a SnO(101) overlayer. For the $1\times 2$ phase, a combination of STM and noncontact AFM images point to an added-row morphology.