Biomedical Engineering Reference
In-Depth Information
Table 7.13
Molecular dipole moments μ (in Debye) and global polarizabilities α
(in Bohr3) of BFPF Green Fluorescent Protein Chromophore calculated with the
M06, M06L, M06-2X and M06-HF density functionals and the MIDIY+ basis set.
Property
M06
M06L
M06-2X
M06-HF
μ
5.7126
5.4969
5.6282
6.1836
α
247.21
257.99
242.64
233.25
7.3.5
HOMO and LUMO Orbitals
h e Highest-Occupied Molecular Orbital (HOMO) and Lowest-Occupied
Molecular Orbital (LUMO) were extracted from the calculations and visu-
alized using the Chemcrat Program - Revision 1.6 [49].
h e HOMO and LUMO orbitals of the BFPF Green Fluorescent Protein
Chromophore molecule calculated with the M06, M06L, M06-2X and
M06-HF density functionals and the MIDIY+ basis set are shown in
Figure 7.14.
7.3.6 Chemical Reactivity
Within the conceptual framework of DFT [18, 30], the chemical potential
μ
, which measures the escaping tendency of electron from equilibrium, is
dei ned as:
E
N
(7.10)
vr
()
where
χ
is the electronegativity.
h e global hardness η can be seen as the resistance to charge transfer:
2
1
2
E
N
(7.11)
2
vr
()
Using a i nite dif erence approximation and Koopmans' theorem [36-39],
the above expressions can be written as:
1
1
(
IA
)
(
)
(7.12)
L H
2
2
