Cubane and cubanoid: Structural, optoelectronic and thermodynamic properties from DFT and TD-DFT method

Area of Science:

• Computational Chemistry
• Materials Science
• Quantum Chemistry

Background:

• Cubane (C8H8) is a strained polycyclic hydrocarbon.
• Exploring derivatives (cubanoids) with heteroatoms can yield novel materials.
• Understanding their properties is crucial for potential applications.

Purpose of the Study:

• To investigate the structural, electronic, and optical characteristics of cubane and its substituted derivatives (cubanoids).
• To assess the stability and potential for spontaneous synthesis of these novel molecules.
• To identify cubanoids with desirable electronic and optical properties for further research.

Main Methods:

• Density Functional Theory (DFT) was employed to calculate structural, electronic, and vibrational properties.
• Time-Dependent Density Functional Theory (TD-DFT) was used for optical absorption calculations.
• Thermodynamic properties were extrapolated to predict synthesis feasibility.

Main Results:

• Cubanoids with substituted Nitrogen, Phosphorus, Boron, Silicon, Arsenic, Antimony, or Bismuth atoms were studied.
• All investigated structures demonstrated exceptional stability, indicated by positive vibrational frequencies.
• HOMO-LUMO gaps ranged from 1.87 eV to 5.61 eV, with five structures showing visible light absorption.
• Thermodynamic analysis suggests spontaneous synthesis is possible for several cubanoids, with some feasible below 400 K and one at room temperature.

Conclusions:

• Cubanoids exhibit remarkable stability and tunable electronic properties.
• Several cubanoid structures show potential for optical applications due to visible light absorption.
• The predicted spontaneous synthesis at accessible temperatures highlights their potential for experimental realization.