Publication at Faculty of Mathematics and Physics |

2011

The rate coefficient of the ternary association reaction H(+) + 2H(2) -} H(3)(+) + H(2) has been measured at a temperature of 11 K using a 22-pole ion trap. The measurements were made over the density range of 0.5-10 x 10(13) cm(-3) using normal hydrogen (with 1/4 p-H(2) and 3/4 o-H(2)).

We measured an apparent binary reaction rate coefficient and from the obtained linear dependence on the hydrogen density we calculated the ternary reaction rate coefficient k(3) = (3 +/- 1) x 10(-29) cm(6) s(-1). From the measured data we can deduce that there exists very slow radiative association with the rate coefficient of the order of k(r) less than or similar to 3 x 10(-16) cm(3) s(-1) at 11 K.