| Popis: |
The temperature dependences of the heat capacities C p ,m o for 1-1 complexes of dimethylzinc with dimethylselenium and of dimethylzinc with dimethyltellurium have been studied between 13.25 and 330 K in a vacuum adiabatic calorimetric cryostat within 0.2 per cent. Temperatures and enthalpies of melting of the complexes as well as characteristics of the glassy complex (CH 3 ) 2 Zn·Te(CH 3 ) 2 , i.e. the glass transition temperature T gt o , the increase in the molar heat capacity on devitrification ΔC p ,m o ( T gt o ), the zero S gt o (0) and configurational entropy S conf o , and the difference of zero enthalpies for the complex in the glassy and the crystalline states { H gt o (0)− H cr o (0)} have been determined. From the values obtained the thermodynamic functions: Δ 0 T H m o , Δ 0 T S m o , and Φ m o have been calculated from T = 0 to 330 K, and the thermodynamic quantities for the processes: (CH 3 ) 2 Zn(l) + (CH 3 ) 2 Se(l) = (CH 3 ) 2 Zn·Se(CH 3 ) 2 (l) and (CH 3 ) 2 Zn(l) + (CH 3 ) 2 Te(l) = (CH 3 ) 2 Zn·Te(CH 3 ) 2 (l) have been estimated also at T = 298.15 K and p = 101.325 kPa. |
