Electronic spectral data

G. W. Wheland, Advances in Organic Chemisty, 2nd ed., John Wiley Sons, Inc., New York, 1949, p. 42 Organic Electronic Spectral Data, Vol. 1, Interscience Pubflshers, Inc., New York, 1960, p. 545. 

An extensive list of visible and UV peaks is given in Organic Electronic Spectral Data , Wiley, New York. Twenty-six volumes have appeared so far, covering the literature through 1984. 

Although coordination of the heterocyclic nitrogen does not occur, two cobalt(II) complexes of 3-hydroxy-5-hydroxymethyl-2-methyl-4-formylpyridine have been isolated with stereochemistry [Co(34-H)A] 2H2O (A = NO3, OAc) [173], For both complexes coordination is ONS (deprotonated phenolic oxygen), but magnetic or electronic spectral data are not included. 

Table 2.4 Experimental and PPP-MO calculated electronic spectral data for azobenzene and the isomeric amino derivatives...

Table 2.4 shows a comparison of the experimental and PPP-MO calculated electronic spectral data for azobenzene and the three isomeric monoamino derivatives. It is noteworthy that the ortho isomer is observed to be most bathochromic, while the para isomer is least bathoch-romic. From a consideration of the principles of the application of the valence-bond approach to colour described in the previous section, it might have been expected that the ortho and para isomers would be most bathochromic with the meta isomer least bathochromic. In contrast, the data contained in Table 2.4 demonstrate that the PPP-MO method is capable of correctly accounting for the relative bathochromicities of the amino isomers. It is clear, at least in this case, that the valence-bond method is inferior to the molecular orbital approach. An explanation for the failure of the valence-bond method to predict the order of bathochromicities of the o-, m- and p-aminoazobenzenes emerges from a consideration of the changes in 7r-electron charge densities on excitation calculated by the PPP-MO method, as illustrated in Figure 2.14. 

Table 5 Electronic spectral data for selected tacn sandwich complexes of Ni11.

Table 6 Electronic spectral data for selected Ni11 complexes of donor-substituted tacn ligands.

Table3. LMCT electronic spectral data for [TcNX4] and [M0OX5]- (X=Cl,Br) [118]...

Kamlet, M. J., M. E. Jones, J.-L. M. Abboud, and R. W. Taft. 1979. Linear Solvation Energy Relationships. Part 2. Correlations of Electronic Spectral Data for Aniline Indicators with Solvent tt and 3 Values. J. Chem. Soc., Perkins Trans. 2, 342. 

The M(VI) oxidation state is represented in the 4d series by the hexafluorides, MFg, of the elements Mo, Tc, Ru, and Rh. All are obtained by direct fluorination of the metal and are unstable powerfully oxidising species — once again the instability seems most marked at the end of the series. Unfortunately hardly any electronic spectral data exist. The first charge-transfer band of the d°MoF(s has been located at 54 kK. (42), and a study of the vibrational spectrum of RuF6 (43) revealed electronic bands at 1.95 and 1.4 kK., which are probably the F2, r5 Ti, and /13,... 

Given the relatively small amount of electronic spectral data available at the present time, and the large variation in the spectral profiles found with different metal end-groups, we have chosen to present the available data in a periodic fashion. We also note that extensive optical studies have been described for polymeric materials with poly-yndiyl repeat units - although further discussion is not appropriate here. 

The presence of jr(CC)-5(MM)- r(CC) conjugation in dimetallapoly-ynes of the type M2(CCR)4(PMe3)4 has been inferred from Raman and electronic spectral data. In turn this may lead to donor (D)-acceptor (A) interactions in... 

Table 2. Electronic spectral data on C04(p.3-O)4(p.-O2CMe)4(py)4 in various solvents...

Electronic spectral data for selected pyridoazepine bases and their salts can be found in Tables 11 and 12, respectively. Data have additionally been reported with reference to cyclic diimide 32 (64CB1548), to homoberbines 157a and b and 158 (69HCA1228) as well as 160 and 161 (69JC874), and to hydroperchlorates, for instance, of homoberbine 209b (87LA639). 

Organic Electronic Spectral Data, Vols. 1-4, Interscience, New York, 1960-1963. 

Electronic Spectral Data for Some Nickel(III) Macrocyclic Complexes... 

Electronic spectral data corresponding to the 4242g->472g(F) and 4A2g- 4T[g(F) electronic transitions in a number of azido-chromium(III) complexes are compiled in Table 71. 

Tables of experimental data for monosubstituted (71PMH(3)67, p. 74) and polysubstituted (B-64MI30400) pyrroles are available (see also B-74MI30400) the reader s attention is also directed to the general compilation (by molecular formula) of Organic Electronic Spectral Data .

The basic idea is illustrated in Figure 1 as presented by Schrauzer.6 A more detailed MO description by Herman et al.m of the dithiolene and SacSac complexes of Ni shows good correlation with the observed electronic spectral data as well as the electrochemical results and thus substantiates the merits of the even/odd classification. Considering only the frontier orbitals (Figure 2), we see that the LUMO of the dithiolene correlates with the HOMO of the SacSac series and the scheme easily explains the acceptor properties found in most of the dithiolenes as well as their absence in the SacSac compounds. 

Thyagarajan, Organic Electronic Spectral Data , J. Wiley Sons, NY (1956—continuing)... 

The formation of amino-substituted disilenes 18 and 19 was also confirmed in similar experiments using 21 and 22 (equations 6 and 7, respectively). Broad bands growing at 395 and 408 nm, respectively, were observed. Absorption maxima of several transient disilenes are summarized in Table 2, in which the absorption spectral data of the recently prepared (trimethylsilylmethyl)trimethyldisilene30 is also included. The electronic spectral data of stable disilenes are well documented8. 

The octahedral iodo or perchlorato compounds of MeNNAsEt have anomalous magnetic moments due to a high-spin low-spin equilibrium. The low-spin CoLI2 (L = NNAs or NNAsEt) have moments of 2.48—3.03 BM, and in conjunction with the electronic spectral data which are inconsistent with tetrahedral or five-co-ordinate geometry, this suggests that the compounds may be rare examples of planar cobalt(n). 

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