The adsorption of two very different adsorbates, gold and oxygen, induce the formation of a ( 3 x 1) surface structure on both W( 1 1 2) and Mo( 1 1 2). In spite of similar adsorbate unit cells, the surface electronic structure, derived from photoemission, exhibits pronounced differences for the two adsorbates. Indeed, both experiment and simulations indicate substantial changes in electronic structures of ( 1 x 1) and ( 3 x 1) gold overlayers supported by highly anisotropic ( 1 1 2) plane. We speculate that ( 3 x 1) is a favored periodicity in the atomic rearrangement of the ( 1 1 2) surfaces of molybdenum and tungsten due in part as a result of the initial state band structure of these surfaces. (c) 2008 Elsevier B. V. All rights reserved.