| 摘要 |
Semi-conducting compounds having the formula Cd4Y2X3, in which X is F, Cl, Br or I and Y is N, P, As, Sb or Bi, are prepared by heating stoichiometric quantities of reactants according to the equation 9CdX2 + 5Cd3Y2 + 2Y --> 6Cd4Y2X3 at 500-550 DEG C. for up to 24 hours in a sealed quartz tube or, where Y is nitrogen, in a nitrogen atmosphere. The reactant Cd3Y2 is prepared by reacting stoichiometric quantities of Cd and Y in a sealed tube or in a nitrogen atmosphere where Y is N. Advantageously, the sealed tube is subject to a temperature gradient so that crystals of Cd4Y2X3 form at the cooler end. The compounds of the invention are isomorphous, having a nearly face-centered cubic arrangement of cadmium atoms. They melt incongruently below 600 DEG C. |
