Heat capacity values of Se4 g at

All available heat capacity values of Se4(g) at 298.15 K are based on estimated quantities and are summarised in Table V-8. The heat capacity value attributed to [84PUP/RUS] was calculated by the review from the estimated molecular parameters reported in the paper. 

Se4(g) is a minor species in selenium vapour and the situation is even worse than for Se3(g) with respect to fragmentation problems. The evaluation of thermodynamic data for Se4(g) has therefore been avoided except in three studies, summarised in Table V-9, where the investigators thought the fragmentation was under control. The study of Keller [70KEL] is the only one in which the fragmentation has been monitored properly and the review selects from this study  

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