Evaluation on thermodynamic properties of Cs-B-O compounds using DFT calculations

Suzuki, Chikashi 

It is shown that boron (B), BWR control materials, can cause a chemical reaction with Cs to form Cs-B-O compounds and affect the chemical behavior of Cs during SA, but the findings are limited. We evaluated the thermodynamic properties of CsBO as a Cs-B-O compound using DFT calculations and lattice vibration calculations. The phonon density of states of CsBO calculated by lattice vibration calculations indicate that the lattice vibration calculations were performed appropriately with the most stable structure because no imaginary component of the lattice vibration frequency is found. The thermodynamic characteristics such as the specific heat of CsBO, furthermore, were calculated by quasi-harmonic approximation. These non-empirical methods made it possible to calculate the thermodynamic properties of CsBO, which had not been measured so far.