2021, №1

сс. 77-89

Diagnostics of the Critical State of Carbon Dioxide

2021, №1

сс. 77-89

Цитировать

Ju.A. Chaikina, S.Ya. Umanskii

Key words: statistical physics, critical phenomena, Rayleigh light scattering

For the first time, the temperature dependence of the density variance and the correlation
length of critical density fluctuations is determined from the experimental data on small-angle
light scattering by critical CO2. It is found that at critical density of CO2 in the temperature
range 10-8 Tc < |T - Tc| < 10-4 Tc (where Tc is the critical temperature) the correlation
length of density fluctuations decreases by 20 % as the critical point is approached. The
value of density variance shows no power-law-type divergence: it remains practically constant
in the temperature ranges T > Tc and T < Tc, but undergoes a 25 % stepwise change when
passing through the critical point, likely due to the peculiarities of the experiment setting up.

doi:10.1134/S1990793121080029