Table 3.

Energy of HOMO/LUMO orbitals and other reactivity descriptors.

Molecular Descriptor	RA	RA-Li	RA-Na	RA-K
HOMO energy/eV	−5.774	−5.788	−5.641	−5.558
LUMO energy/eV	−2.170	−1.871	−1.746	−1.698
HOMO-LUMO energy gap/eV	3.604	3.917	3.894	3.860
Electron affinity (A)/eV	2.170	1.871	1.746	1.698
Ionization potential (I)/eV	5.774	5.788	5.641	5.558
Chemical hardness (η)/eV	1.802	1.959	1.947	1.930
Chemical softness (s)/eV	0.277	0.255	0.257	0.259
Chemical potential (μ)/eV	−3.972	−3.830	−3.693	−3.628
Electronegativity (χ)/eV	3.972	3.830	3.693	3.628
Electrophilicity index (ω)/eV	4.378	3.744	3.503	3.410
Nucleophilicity index (N)/eV	3.713	3.699	3.847	3.930

I = −E_HOMO; A = −E_LUMO; χ = (I + A/2); η = (I − A)/2; s = 1/2η; μ = −(I + A)/2; ω = μ²/2η; N = E_{HOMO(nuclefil)} − E_HOMO(TCE); TCE−tetracyanoethylene.