Dissociative recombination of H₃⁺and D₅⁺

Abstract

Compared with earlier years, the dissociative recombination of H 3 + has not been very actively studied in recent years. New results from afterglow experiments are quoted and compared with results from ion storage rings and theory. New results for D 5 + are discussed. This article also contains some historical remarks on hydrogen and its importance for the advancement of physics and chemistry. This article is part of a discussion meeting issue ‘Advances in hydrogen molecular ions: H 3 + , H 5 + and beyond’.

New Bistable Solutions in Molecular Cloud Chemistry: Nitrogen and Carbon Autocatalysis

“…In Paper I, the + H 3 electron recombination rate coefficient (α 3 ) was found to play a role in the cause of the bistability of oxygen chemistry; the calculations presented here also address this issue (Sections 3.2 and 3.3). Although α 3 (T) is now very well constrained, both experimentally and theoretically (McCall et al 2003;Jungen & Pratt 2009;Larsson 2019), we have used two values that bracket the experimental value at 10 K: α 3 (10 K) = 1.0 × 10 −6 cm 3 s −1 and 1.0 × 10 −7 cm 3 s −1 . Except where stated, all models were first computed using the higher α 3 .…”

Hydrogen molecular ions: H 3 + , H 5 + and beyond

“…The rate of dissociative recombination (DR) of H + 3 was long a subject of controversy, which appears now to be substantially resolved [71]. Conversely measurements of the DR rate H + 5 , or more precisely for D + 5 , suggest that the situation is more straightforward, with a simple picture of the recombination process capturing the essential physics of the problem, as discussed by Larsson [72,73].…”