We discuss a very simple model of a 1-d disordered lattice, in which all the electronic eigenstates are extended. The nature of these states is examined from several viewpoints, and it is found that the eigenfunctions are not Bloch functions although they extend throughout the chain. Some typical wavefunctions are plotted. This problem originated in our earlier study of extended states in the quasiperiodic copper-mean lattice [ Sil, Karmakar, Moitra and Chakrabarti, Phys. Rev. B (1993)]. In the present investigation extended states are found to arise from a different kind of correlation than that of the well-known dimer-type. PACS Nos.: 71.25.-s, 71.55.JvFollowing the original work of Anderson , there is a vast literature on the nature of electronic eigenfunctions in disordered systems . Over the past decade, the scaling approach has been successfully utilised to elucidate the problem of the dimensional dependence of the localisation and related problems in such systems [3-5]. It is now part of the folklore that in 1-
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