Hassium Properties

Chemical properties of Hassium were studied with isotopes ²⁶⁹Hs and ²⁷⁰Hs, which were syntheses in the fusion reaction between Curium-248 and Magnesium-26.

²⁴⁸Cm + ²⁶Mg -> ²⁶⁹Hs + 5n

Synthesized Hassium isotopes thermalized in a stream of Helium + Oxygen gases and then heated to 600°C with subsequent formation of HsO₄, with further registering of the nuclear decays in a low-temperature thermochromatographic detection system (an array of 12 pairs of silicon detectors with temperature gradient from -20°C at the entrance and -196°C at the exit, see Picture) which can adsorb molecules at a positions related with their volatility.



HsO₄ was adsorbed at about -44°C. As a standard was used ¹⁷²OsO₄ (¹⁵²Gd(²⁶Mg, 6n)¹⁷²Os) yielding adsorption temperature of around -82°C. The adsorption enthalpies, calculated were -46 kJ/mol and -39 kJ/mol for HsO₄ and OsO₄, respectively. In this experiment Hassium behavior with formation of a very volatile tetroxide is typical for the group 8 of the periodic table.

The relativistic effect on the valence electron shell is override the periodic law for super heavy chemical elements, especially for transactinides. For the first two transactinides Rutherfordium (element 104) and Dubnium (element 105), the chemical properties are significantly differ from those expected from the periodic law. The studies of chemical properties of Hassium, as well Bohrium shows that these two transactinides behave accordingly to their position in the periodic table and relativistic effect do not disturb the periodic law.