Programme

P.16 -- Poster, VCTP-44

Date: Tuesday, 30 July 2019

Time: 08:30 - 10:00

Debye model for heat capacity of liquid water at normal condition

Tran Thi Nhan (1) and Le Tuan (2)

(1) Hanoi University of Industry, 298-Cau Dien Road, Bac Tu Liem Dictrist, Hanoi, Viet Nam (2) Hanoi Science and Technology, 1-Dai Co Viet Road, Hanoi, Viet Nam

Debye temperature of liquid water is determined from the modified phonon-polariton model. The decrease in the value of Debye temperature with rising temperature is also pointed out. According to the modified phonon-polariton model, the longitudinal sound wave could travel in the system with frequency range from zero to Debye frequency whereas the two traverse acoustic modes propagate on the hydrogen bonding network from Frenkel frequency to the Debye frequency. Using Debye theory, the internal energy of liquid water is given in the explicit form. Therefore, the heat capacity of liquid water can be determined in the similar way which is applied for solid materials. The model shows that the heat capacity of liquid water is almost independently of the temperature in the range from 273.15 K to 373.15 K, in agreement with empirical observation.

Presenter: Tran Thi Nhan