Table 3.

Adiabatic energies, E^a (S₁) (in eV), fluorescence energy, E_fl. (in eV), oscillator strength, f, dipole moment, µ_e, and carbonyl bond distances of the S₁^LE(π,π^∗), S₁^LD(n,π*) and S₁^LU(n,π*) excited–state forms for three flavin derivatives optimized at the ADC(2)/cc-pVDZ theory level.

State	S1LE(π,π*)	S1LD(n,π*)	S1LU(n,π*)	S0
Molecule 1, roatmer H-bonded
Ea (S1)	2.374 eV	2.389 eV	2.043 eV	0.00
Efl.	1.71 eV (1.90 eV)	1.24 eV	0.47 eV	–
ffl.	0.1112	0.0000007	0.000004	–
µe	6.0 D	4.3 D	10.3 D	6.5 D
R1(C(2)-O)	1.241 Å	1.225 Å	1.379 Å	1.222 Å
R2(C(4)-O)	1.227 Å	1.368 Å	1.222 Å	1.223 Å
R3(C(4’)H—N(1))	2.488 Å	2.502 Å	2.558 Å	2.487 Å
Molecule 1, rotamer non-H-bonded
Ea (S1)	2.465	2.441	2.074	0.026 eV
Efl.	1.93 eV (2.09 eV)	1.27 eV	0.46 eV	–
ffl.	0.1581	0.000003	0.000004	–
µe	7.4 D	4.0 D	10.5 D	6.7 D
R1(C(2)-O)	1.234 Å	1.226 Å	1.379 Å	1.221 Å
R2(C(4)-O)	1.229 Å	1.367 Å	1.222 Å	1.223 Å
R3(C(4’)H—N(1))	5.264 Å	5.243 Å	5.266 Å	5.159 Å
Molecule 2
Ea (S1)	2.443 eV	2.376 eV	2.028 eV	0.0 eV
Efl.	1.98 eV	1.22 eV	0.43 eV	–
ffl.	0.1801	0.0000006	0.000003	–
µe	7.9 D	4.3 D	10.2 D	6.8 D
R1(C(2)-O)	1.234 Å	1.220 Å	1.380 Å	1.221
R2(C(4)-O)	1.229 Å	1.368 Å	1.222 Å	1.223
Molecule 3
Ea (S1)	2.474 eV	2.378 eV	2.038 eV	0.0 eV
Efl.	1.93 eV	1.22 eV	0.433 eV	–
ffl.	0.1679	0.0000006	0.00003	–
µe	7.8 D	3.4 D	9.6 D	6.6 D
R1(C(2)-O)	1.235 Å	1.224 Å	1.379 Å	1.220 Å
R2(C(4)-O)	1.228 Å	1.368 Å	1.222 Å	1.223 Å
Molecule 4
Ea (S1)	2.531 eV	2.384 eV	2.051 eV	0.00
Efl.	1.87 eV	1.22 eV	0.44 eV	–
ffl.	0.1342	0.0000006	0.000003	–
µe	8.9 D	3.2 D	10.0 D	7.6 D
R1(C(2)-O)	1.237 Å	1.224 Å	1.380 Å	1.220 Å
R2(C(4)-O)	1.228 Å	1.368 Å	1.222 Å	1.223 Å

Single point calculation of E_fl at the CC2/aug-cc-pVDZ level are given in parenthesis