Fragmentation by β-Decay in Tritium-Labelled Compounds, (II)

Abstract

The behaviors of CH₃He⁺ and C₂H₅He⁺ formed by the decay of CH₃T and C₂H₅T were studied theoretically using the STO-3G molecular orbital method and was compared with that of HHe⁺ in the decay of HT. It was clearly shown that the ground state daughter ions CH₃He⁺ and C₂H₅He⁺ dissociate instantly to give CH₃ ⁺ and C₂H₅ ⁺ because their potential energy curves are repulsive, whereas the daughter ion HHe⁺ in the ground state does not dissociate. The transition probability to the ground state ions of CH₃He⁺ and of C₂H₅He⁺ are computed to be 66.5 and 64.8%, respectively. These values are in fairly good accordance with those obtained experimentally.

KEYWORDS:

• tritium labelled alkanes
• beta decay
• tritium
• fragmentation
• molecular orbital theory
• potential energy
• CH₃He⁺
• C₂H₅He⁺
• transition probabilities CH₃T
• C₂H₅T
• accuracy
• comparative evaluation
• daughter products
• tritium labelled compounds