Negative heat capacities and first order phase transitions in nuclei and other mesoscopic systems

摘要

The origin of predicted and observed anomalies in caloric curves of nucleiand other mesoscopic systems is investigated. It is shown that astraightforward thermodynamical treatment of an evaporating liquid drop leadsto a backbending in the caloric curve and to negative specific heats in the twophase coexistence region. The cause is found not in the generation ofadditional surface, but in the progressive reduction of the drop's radius, andsurface, with evaporation.