text: A well-studied class of solid-state compounds related to the chalcohalides are molybdenum clusters of the type AMoX with X sulfur or selenium and A an interstitial atom such as Pb.  These materials, called Chevrel phases or Chevrel clusters, have been actively studied because they are type II superconductors with relatively high critical fields.  Such materials are prepared by high temperature (1100 °C) reactions of the chalcogen and Mo metal.  Structurally related, soluble analogues have been prepared, e.g., MoS(PEt).