Hydrogen molecular ions: H₃⁺, H₅⁺ and beyond

Area of Science:

• * Physics, Chemistry, and Astronomy
• * Astrochemistry and Molecular Physics

Background:

• * Spectroscopic detection of H₃⁺ in space three decades ago.
• * Significant progress in understanding H_n⁺ (n=3, 5, 7) systems.

Purpose of the Study:

• * To review developments in hydrogen molecular ions.
• * To survey the current state of research in the field.
• * To consider future research directions.

Main Methods:

• * Literature review and synthesis of recent findings.
• * Discussion of spectroscopic and theoretical advancements.
• * Consolidation of knowledge presented at a Royal Society Discussion Meeting.

Main Results:

• * Comprehensive overview of H_n⁺ research.
• * Highlighting interdisciplinary progress in physics, chemistry, and astronomy.
• * Identification of key advancements and challenges.

Conclusions:

• * The field of hydrogen molecular ions has seen remarkable progress.
• * Continued interdisciplinary research is crucial for future discoveries.
• * This review serves as a benchmark for H_n⁺ research and future exploration.