In this situation my question is suppose I have obtained negative PDOS for a particular structure. If I will give this values in the manuscript and send to any journal for publication and if the referee will ask about this then what should I do?
On Sun, Apr 12, 2015 at 3:05 PM, <fthe...@iesl.forth.gr> wrote: > I fully agree with Emilio. > The fact that you find negative PDOS even for s orbitals has to do with > the interactions between those s-orbitals with the orbitals of the other > atoms, which might give small negative contributions. If you select > different orientations of the atoms, you may have different contributions > from the atomic orbitals (since their orientation will not change) and > those negative contributions could (hopefully) absorbed by other positive > contributions. Thus, the PDOS will (hopefully) not be negative. Obviously, > there is not any physical meaning for a negative PDOS. > The problem comes from the physical meaning assigned to the PDOS, which is > exactly the same with the physical meaning assigned to the Mullicken > charges. > Maybe you can get some answers in Roald Hoffmann's book "Solids and > Surfaces". > > Zacharias Fthenakis > > > The mentioned well-known problem is related with > > the use of non-orthogonal basis sets. For > > orthogonal ones the PDOS is definite positive, > > which is what people expect. But for > > non-orthogonal ones that is not the case > > (although negatve values tend to be small > > since the diagonal bit dominates and that one > > is positive) > > > > Emilio > > > > -- > > Emilio Artacho > > CIC Nanogune Consolider, and Cavendish Laboratory, University of > Cambridge > > Tolosa Hiribidea 76, E-20018 Donostia - San Sebastián, Spain, > > e.arta...@nanogune.eu, +34 943 574 4000, http://theory.nanogune.eu > > > > On 12 Apr 2015, at 09:53, fthe...@iesl.forth.gr wrote: > > > >> This is a well known "problem", but has not to do with SIESTA. It has to > >> do with the physical meaning of the decomposition of DOS to PDOS. If you > >> decompose to orbitals with different orientation you may probably not > >> have > >> those "problems". > >> > >> Zacharias Fthenakis > >> > >>> Dear siesta users, > >>> Has any one encountered the problem of negative value of projected DOS > >>> which is calculated with the mprop utility? It seems quite unreasonable > >>> for me, any ideas how this come out? > >>> > >>> Best regards, > >>> Bing > >> > >> > >> ********************************************************* > >> Dr Zacharias G. Fthenakis > >> Research Associate > >> Institute of Electronic Structure and Laser (I.E.S.L.) > >> Foundation for Research and Technology Hellas (FO.R.T.H.) > >> Vassilika Vouton P.O. Box 1527 71003 Heraklion Crete Greece > >> Phone +30 2810 391824 > >> FAX +30 2810 391305 > >> webpage: http://esperia.iesl.forth.gr/~fthenak > >> ********************************************************** > >> > > > > > ********************************************************* > Dr Zacharias G. Fthenakis > Research Associate > Institute of Electronic Structure and Laser (I.E.S.L.) > Foundation for Research and Technology Hellas (FO.R.T.H.) > Vassilika Vouton P.O. Box 1527 71003 Heraklion Crete Greece > Phone +30 2810 391824 > FAX +30 2810 391305 > webpage: http://esperia.iesl.forth.gr/~fthenak > ********************************************************** > > -- *Senior research fellow Dept. of Physics, University of Calcutta Kolkata- 700009, West Bengal, India.* * Ph no-+91-9830512232*
