TD-DFT calculations

Phenylperoxy radical has similarly been a topic of experimental and theoretical interest. Tokmakov et al. " calculated a potential energy surface for phenyl radical and O2 using ab initio G2(MP2) calculations. Weisman and Head-Gordon used time-dependent density functional theory (TD-DFT) calculations to examine the effect of substituents on the phenylperoxy radical s UV-vis absorption spectrum. " Lin and Mebel used ab initio methods to study the phenoxy radical -f O-atom reaction. "... 

These conclusions have been reinforced by at least two recent, detailed theoretical studies using TD-DFT calculations [87,88], which reveal that the proportion of Pt(5d) metal character in the HOMO falls from around 25% for alkyl acetylides (R = n-propyl) to around 10% for phenylacetylide, the tt(C=C-R) character increasing correspondingly. For an aryl acetylide with... 

Therefore, the excited states responsible for the emissions were throughout to be located on the gold and silver atoms in each complex. The theoretical TD-DFT calculations coincided with these results and showed... 

Very recently, time-dependent density functional theory (TD-DFT) calculations have been applied to bis-diamine as well as tris-diamine Co(III) or Rh(III) complexes spanning the entire experimental spectral region including the charge transfer... 

Finally, it is worth mentioning that both complexes luminesce in the solid state both at room temperature and at 77 K, showing different luminescent behavior, the dioxane derivative being one of the still scarce blue luminescent materials. In contrast, the acetone complex is also luminescent in solution and shows a solvent dependence on the emission. Luminescence and conductivity measurements suggest that the Tl- -Tl interaction also exists in solution (probably stabilized by solvent molecules) and TD-DFT calculations seem to indicate that this interaction is responsible for luminescence in this case. This contrasts with other pentahalophenyl Au/Tl complexes, in which the optical properties are associated with the Au- -Tl contacts.149,151-154... 

Two typical examples of lowest allowed singlet states of Re complexes are shown in Fig. 7, the leftmost column TD-DFT calculated maps of difference electron density of [Re(py)(CO)3(bpy)]+ and [Re(Cl)(CO)3(bpy)] clearly show that the electron density is transferred from Re(CO)3 and Re(Cl)(CO)3 moieties to the bpy ligand, respectively. No contribution from nn IL(bpy) excitation is discernible. 

Fluorescence from singlet excited states of [Re(X)(CO)3(bpy)] (X = Cl, Br, I) and [Re(Etpy)(CO)3(bpy)]+ appears concomitantly with 400 mn, 80 fs pulse excitation as a very broad band peaking at -530 nm (in Chap. 1 of this book). The large instantaneous fluorescence Stokes shift and broadness indicate a femtosecond energy dissipation and ultrafast population of many vibrational modes. TD-DFT calculations [10]... 

Mixing between CT and jot IL(N,N) characters is not important for the singlet excited states of [Re(L)(CO)3(N,N)]M, for the TL states usually lie well above the optically populated 7CT state. However, the IL-CT mixing becomes much more pronounced in low-lying triplet states of A" symmetry, because the JIL and JCT states lie very close in energy. Most [Re(L)(C()) (polypyridyl) complexes have two low-lying A" triplets of a predominantly IL and CT (i.e., MLCT or MLLCT) characters which occur within the range ca. 0.5 eV wide [10-12, 74, 76], In most complexes, the 3IL state lies above 3CT. TD-DFT calculations show that these states result from linear combinations of jt—ot and HOMO-1—>ji one-electron excitations, which introduce the IL and CT characters, respectively ... 

Transition metal-carbonyl-diimine complexes [Ru(E)(E ) (CO)2(a-diimine)] (E, E = halide, alkyl, benzyl, metal fragment a-diimine = 1, 4-diazabutadiene or 2,2 -bipyridine) are widely studied for their unconventional photochemical, photophysical, and electrochemical properties. These molecules have a great potential as luminophores, photosensitizers, and photoinitiators of radical reactions and represent a challenge to the understanding of excited-state dynamics. The near-UV/visible electronic spectroscopy of [Rn(X)(Me)(CO)2(/Pr-DAB)] (X = Cl or I iPr-DAB = A,A -di-isopropyl-l,4-diaza-l,3-butadiene) has been investigated throngh CASSCF/C ASPT2 and TD-DFT calculations on the model complexes [Ru(X)(Me)(CO)2(Me-DAB)] (X = Cl or I) (Table 2). 

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