The Tip Temperatures of Freely Growing High-Purity Succinonitrile Dendrites

The tip temperatures of “freely” growing, high-purity succinonitrile dendrites have been estimated here using the Ivantsov solution and space shuttle dendritic growth data. The estimated tip temperatures are found to be significantly higher than the currently accepted equilibrium melting point of succinonitrile (58.083°C or 331.24 K), for a large majority of these experiments. Because a solid cannot grow above its melting point, it is suggested that this discrepancy is due to dendritic side-branching effects that should be included, in a systematic manner, in the analysis of the growth data. The earth-based dendritic growth data reveal the same discrepancies.