Figure 1

Schematic diagram of the levels involved in the DR of $\mathrm{H}_3{}^{+}$ with an electron. With the linear Jahn-Teller (JT) effect, only $\Delta v=\pm 1$ processes are allowed, and the coupling between the $v=0$ and 1 levels is shown with the double arrows. The arrows pointing to the right (left) indicate electron capture (JT vibrational autoionization), respectively. The scaled matrix element coupling the continuum and Rydberg states is also indicated. Inset: nuclear displacements corresponding to the degenerate JT vibrational mode. The dotted arrow indicates the phase of the electronic factor $e^{i\Lambda \varphi }$.Reuse & Permissions

Figure 2

The DR rate coefficient of $\mathrm{H}_3{}^{+}$ as a function of collision energy. Circles: experiment [21] with $\Delta E_{\perp }=0.5\mathrm{meV}$ and $\Delta E_{\parallel }=0.025\mathrm{meV}$; Solid line: present results, unconvolved. Dotted line: present results, convolved with $\Delta E_{\perp }=0.5\mathrm{meV}$ and $\Delta E_{\parallel }=0.025\mathrm{meV}$; Dashed line: theoretical data [9], convolved with $\Delta E_{\perp }=2\mathrm{meV}$ and $\Delta E_{\parallel }=0.1\mathrm{meV}$.Reuse & Permissions

Figure 3

The DR rate coefficient of an electron and $\mathrm{H}_3{}^{+}$, ${\mathrm{H}}_2{\mathrm{D}}^{+}$, ${\mathrm{D}}_2{\mathrm{H}}^{+}$, and $\mathrm{D}_3{}^{+}$ as a function of collision energy. $\mathrm{H}_3{}^{+}$ (black) Circles: experiment [21] with $\Delta E_{\perp }=0.5\mathrm{meV}$ and $\Delta E_{\parallel }=0.025\mathrm{meV}$; Solid line: present results, convolved with $\Delta E_{\perp }=0.5\mathrm{meV}$ and $\Delta E_{\parallel }=0.025\mathrm{meV}$; Dashed line: theoretical results [9] convolved with $\Delta E_{\perp }=2\mathrm{meV}$ and $\Delta E_{\parallel }=0.1\mathrm{meV}$, and with a rotational temperature of 1000 K. ${\mathrm{H}}_2{\mathrm{D}}^{+}$ (blue) Inverted triangles: experiment [22]; Solid line: present results, convolved with $\Delta E_{\perp }=10\mathrm{meV}$ and $\Delta E_{\parallel }=0.2\mathrm{meV}$; Dashed line: theoretical results [7] convolved with $\Delta E_{\perp }=10\mathrm{meV}$ and $\Delta E_{\parallel }=0.2\mathrm{meV}$. ${\mathrm{D}}_2{\mathrm{H}}^{+}$ (red) Diamonds: experiment [23] with $\Delta E_{\perp }=12\mathrm{meV}$ and $\Delta E_{\parallel }=0.07\mathrm{meV}$; Solid line: present results, convolved with $\Delta E_{\perp }=12\mathrm{meV}$ and $\Delta E_{\parallel }=0.07\mathrm{meV}$; Dashed line: theoretical results [7] convolved with $\Delta E_{\perp }=10\mathrm{meV}$ and $\Delta E_{\parallel }=1\mathrm{meV}$. $\mathrm{D}_3{}^{+}$ (green) Triangles: experiment [22]; Solid line: present results, convolved with $\Delta E_{\perp }=40\mathrm{meV}$ and $\Delta E_{\parallel }=6\mathrm{meV}$; Dashed line: theoretical results [8] convolved with $\Delta E_{\perp }=40\mathrm{meV}$ and $\Delta E_{\parallel }=6\mathrm{meV}$.Reuse & Permissions