On the possibility of fluorescence from twisted intramolecular charge transfer states of 2-dimethylamino-6-acylnaphthalenes. A quantum-chemical study

Thermochromic Shifts of Absorption and Fluorescence Spectra and Excited State Dipole Moment of PRODAN

“…However, best to our knowledge, no such measurements are known for PRODAN. The experimental values of /i g obtained by us (Table 2) may be only compared with the value of /i g = 3.77 D calculated by the CNDO/2 method [14], which is, however, distinctly higher than that determined by us.…”

“…and ji e depend not only on m ] and m 2 but also on the Onsager interaction radius a. data [1] and a = 4.6 A based on the calculation of the spherical cave volume being a sum of all volumes of atoms [14]. In the present work, /i g and /i e are determined for both values of a and they are listed in Table 2.…”

“…It is seen that the ratio /i e /,u g = 2.7 determined by the thermochromic method is smaller than that determined from the solvatochromic method (/x e //i g = 3.0). (14) and (15).…”

Ground-and Excited-State Dipole Moments of 6-Propionyl-2-(dimethylamino)naphthalene Determined from Solvatochromic Shifts

“…Assuming a = 4.6 Ä, the calculated Onsager cavity radius of a sphere with the volume being the sum of the volumes of all atoms [18], we obtain now for m x = 2500 cm" 1 and m 2 = 5000 cm" 1 from (7) and ( It is necessary to mention that one determines the dipole moment of a free molecule on the ground state by our theory [8]. In order to eliminate the specific solutesolvent association as a result of the formation of hydrogen bonds, and the formation of solvation shells around the solute molecule in two component solvents (non-polar/polar) it is useful to apply the thermochromic shifts method [10,[19][20][21][22][23].…”

Analysis of fluorescence spectra of PRODAN in protic solvents as the superposition of two Gaussian functions

“…In this context, it is worth mentioning the computational results of Nowak et al [11], by means of the CNDOS method and of Parusel et al [12], with the DFT/SCI method and the AMI/CISD Hamiltonian. One of the two configurations of the excited state is more susceptible to 'hydrogen bond' interactions between solvent molecules [10].…”