Computational Nanochemistry Study of the Molecular Structure and Properties of Chlorophyll a

Table 2

HOMO and LUMO orbital energies (in eV), ionization potentials 𝐼 and electron affinities 𝐴 (in eV), and global electronegativity 𝜒, total hardness 𝜂, and global electrophilicity 𝜔 of chlorophyll a calculated with the M06, M06L, M06-2X, and M06-HF density functionals and the MIDIY and DGDZVP basis sets. The upper part of the table shows the results derived assuming the validity of Koopmans' theorem and the lower part shows the results derived from the calculated vertical 𝐼 and 𝐴.

Property	M06	M06L	M06-2X	M06-HF
HOMO	5.221	4.680	5.897	7.076
LUMO	2.466	2.989	1.973	0.892
𝜒	3.8435	3.8344	3.9349	3.9839
𝜂	2.7550	1.6912	3.9240	6.1840
ω	2.6810	4.3468	1.9729	1.2833
I	6.196	6.145	6.361	6.522
A	1.442	1.479	0.056	1.453
𝜒	3.8190	3.8121	3.2084	3.9874
𝜂	4.7540	4.6660	6.3058	5.0684
ω	1.5339	1.5572	0.8162	1.5685