Designing Metal-Free Organic Superalkalis by Modifying Benzene: a Theoretical Perspective

Using density functional theory, we have designed novel metal-free organic superalkalis by rational modification of the aromatic molecule benzene. The superalkalis exhibit very low ionization energies, even lower than the ionization energy of the alkali metal, cesium. The Hückel’s aromaticity rule is seen to play an important role in the design strategy of the organic superalkali compounds. The superalkalis are devised by replacing the core C atom and the H atoms of benzene with proper substituents. Nitrogen atom is used as core substitution, and two different electron-donating groups, –NH2 and –CH3, are employed to substitute the H atoms. It is noticed that the ionization energies of these organic superalkalis are considerably lower compared to that of the commonly used organic reducing agents. To predict their stability, we have evaluated the binding energy per atom values of the systems. It is also observed that the superalkalis show nonlinear optical property and may have industrial importance.