Aromaticity switching by quantum tunnelling

Area of Science:

• Quantum Chemistry
• Organic Chemistry
• Materials Science

Background:

• Antiaromatic π-conjugated systems are crucial for studying ultrafast molecular dynamics.
• Quantum tunneling drives molecular rearrangements over degenerate double-well potential surfaces.

Purpose of the Study:

• To computationally investigate π-bond-shifting automerization in specific antiaromatic dinaphthopentalene derivatives.
• To explore the interconversion of aromaticity in these systems driven by quantum tunneling.

Main Methods:

• Utilized computational tools to model molecular behavior.
• Focused on quantum tunneling mechanisms in π-conjugated systems.

Main Results:

• Observed ultrafast carbon tunneling facilitating automerization in dinaphthopentalenes.
• Demonstrated interconversion of local aromatic and antiaromatic ring character near absolute zero.
• Theoretically described a 'Schrödinger's aromaticity cat' state arising from quantum superposition.

Conclusions:

• Antiaromatic systems exhibit unique aromaticity switching via quantum tunneling.
• Coherent preparation could lead to novel quantum states in these molecules.