Hydroquinone aggregates as a thermoelectric switch

The reaction of cis-bis-glycinato copper(II) monohydrate with hydroquinone in the presence of hydrogen peroxide leads to copper(II)-containing hydroge n bonded aggregates having the properties of a thermoelectric switch in the region of 42 to 160 degrees C. The ESR shows evidence of a change in coord ination around the copper centre during the conductivity change of the swit ch. A similar reaction of hydroquinone with copper(II) acetate monohydrate and hydrogen peroxide leads to an aggregate having such a property from roo m temperature to 130 degrees C. The reaction of hydroquinone with tertiary butyl hydroperoxide in the presence of a catalytic amount of cis-bis-glycin ato copper(II) monohydrate gives quinhydrone that possesses semiconducting properties above 100 degrees C. The quinhydrone thus prepared on doping wit h cis-bis-glycinato copper(II) monohydrate shows the properties of a thermo electric switch. (C) 2000 Elsevier Science B.V. All rights reserved.