Subject: Hybrid DFT approach

From: <[email-masked]>
Date: Wed, 08 Feb 1995 15:40:57 +0100 (CET)

Dear net-ters,
   I shold like to add something to the hybrid DFT approaches (B3LYP and so on)
and to have your advice.
The first point is (about the discussion between Johnson and Gaussian 
Inc.) that that the following references could be added to the B3LYP 
bibliografy:

[1] V. Barone, C. Adamo, "Theoretical study of direct and water assisted
isomerization of formaldehyde radical cation.  A comparison between 
density functional and post Hartree-Fock approaches" Chem. Phys. Lett.
224 (1994) 432, erratum ibid. 228 (1994) 499

[2]V. Barone " Inclusion of Hartee-Fock exchange in the density functional
approach. Benchmark computations for diatomic molecules containing H, B, 
C, N, O and F atoms, Chem. Phys. Lett. 226 (1994) 392.

[3] V. Barone " Inclusion of Hartree-Fock exchange in density functional 
methods.  Hyperfine structure of second row atoms and hydrides", J. Chem. Phys.
101 (194) 6834.

[4]V. Barone " Characterization of the potential energy surface of the HO2
molecular system by a density functional approach", J. Chem. Phys. 101 (1994) 
10666.

[5]V. Barone, C. Adamo "Proton transfer in model hydrogen-bonded systems by 
a density functional approach" Chem. Phys. Lett. 231 (1994) 295.

[6]F. Lelj, C. Adamo V. Barone " Role of the Hartree-Fock exchange in
density functional theory.  Some aspects of the conformational potential
energy surface of glycine in the gas-phase" Chem. Phys. Lett. 230 (1994) 189.

[7]V. Barone, L. Orlandini e C. Adamo, "Density functional study of
diborane, dialane and digalane", J. Phys. Chem. 98 (1994) 13185.

[8]V. Barone, C.Adamo, F. Lelj "Conformational behaviour of gaseous glycine
by a density functional approach", J. Chem. Phys. 101 (1995) 366.

[9]C. Adamo V. Barone, F. Fortunelli " Validation of self-consistent hybrid
density functionals for the study of structural and electronic characteristic 
of organic pi-radicals, J. Chem. Phys. 102 (1995) 384.

Please note that at least paper n. 2 is a systematic study.

The second point is on the nature of the hybrid approaches.  
Since there are in the B3LYP method 3 parameters fitted on experimental 
values, should B3LYP be considered a semiempirical method?  

 Ciao Carlo

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