000 03842naaaa2200313uu 4500
001 https://directory.doabooks.org/handle/20.500.12854/70678
020 _aintechopen.80280
024 7 _a10.5772/intechopen.80280
_cdoi
041 0 _aEnglish
042 _adc
072 7 _aPN
_2bicssc
100 1 _aStuyver, Thijs
_4auth
700 1 _aDe Proft, Frank
_4auth
700 1 _aFias, Stijn
_4auth
700 1 _aAyers, Paul
_4auth
700 1 _aGeerlings, P.
_4auth
245 1 0 _aChapter New Insights and Horizons from the Linear Response Function in Conceptual DFT
260 _bInTechOpen
_c2019
506 0 _aOpen Access
_2star
_fUnrestricted online access
520 _aAn overview is given of our recent work on the linear response function (LRF) χrr′ and its congener, the softness kernel srr′, the second functional derivatives of the energy E and the grand potential Ω with respect to the external potential at constant N and μ, respectively. In a first section on new insights into the LRF in the context of conceptual DFT, the mathematical and physical properties of these kernels are scrutinized through the concavity of the E=ENv and Ω=Ωμv functionals in vr resulting, for example, in the negative semidefiniteness of χ. As an example of the analogy between the CDFT functionals and thermodynamic state functions, the analogy between the stability conditions of the macroscopic Gibbs free energy function and the concavity conditions for Ω is established, yielding a relationship between the global and local softness and the softness kernel. The role of LRF and especially the softness kernel in Kohn’s nearsightedness of electronic matter (NEM) principle is highlighted. The first numerical results on the softness kernel for molecules are reported and scrutinized for their nearsightedness, reconciling the physicists’ NEM view and the chemists’ transferability paradigm. The extension of LRF in the context of spin polarized conceptual DFT is presented. Finally, two sections are devoted to ‘new horizons’ for the LRF. The role of LRF in (evaluating) alchemical derivatives is stressed, the latter playing a promising role in exploring the chemical compound space. Examples for the transmutation of N2 and the CC→BN substitution pattern in 2D and 3D carbocyclic systems illustrate the computational efficiency of the use of alchemical derivatives in exploring nearest neighbours in the chemical compound space. As a second perspective, the role of LRF in evaluating and interpreting molecular conductivity is described. Returning to its forerunner, Coulson’s atom-atom polarizability, it is shown how in conjugated π systems (and within certain approximations) a remarkable integral-integrand relationship between the atom-atom polarizability and the transmission probability between the atoms/contacts exists, leading to similar trends in both properties. A simple selection rule for transmission probability in alternating hydrocarbons is derived based on the sign of the atom-atom polarizability.
540 _aCreative Commons
_fhttps://creativecommons.org/licenses/by/3.0/
_2cc
_4https://creativecommons.org/licenses/by/3.0/
546 _aEnglish
650 7 _aChemistry
_2bicssc
653 _aconceptual DFT, linear response function, nearsightedness of electronic matter, alchemical derivatives, molecular conductivity
773 1 0 _0OAPEN Library ID: ONIX_20210602_10.5772/intechopen.80280_417
_7nnaa
856 4 0 _awww.oapen.org
_uhttps://library.oapen.org/bitstream/20.500.12657/49303/1/63326.pdf
_70
_zDOAB: download the publication
856 4 0 _awww.oapen.org
_uhttps://library.oapen.org/bitstream/20.500.12657/49303/1/63326.pdf
_70
_zDOAB: download the publication
856 4 0 _awww.oapen.org
_uhttps://directory.doabooks.org/handle/20.500.12854/70678
_70
_zDOAB: description of the publication
999 _c38058
_d38058