I agree with the previous post, the Harrison text is a great reference to clarify these issues. To a first approximation, one can assume that the antibonding state and conduction band are equivalent. As a qualitative example of this consider the following:
Consider two hydrogen atoms...
Hello all,
I am attemtping to model crystal twinning using DFT methods. In particular I wish to look at the twin energy as a function of twin angle in a hcp system. I am running into difficulty however in attempting to create my repeat unit prior to my calculations. I was wondering if...
Kanato,
As an example, consider GaN-GaP pseudobinary system in the wurtzite phase. In pure GaN, GaP both N and P atoms are terahedrally coordinated to Ga. In a mixed state, these atoms have the same local chemical environment. In that case would it be a valid assumption to neglect the change...
Hello all,
I am looking at the entropy of mixing for a binary AxB1-x alloy and I was wondering, when is it a valid assumption to neglect the contribution arising from the change in vibrational entropy between the mixed and the unmixed state.
Thanks in advance!
Thank you all for all your input. I have thought about this some more and would like to throw out a question concerning my previous post. For a long time it was know through tight-binding calculations that a monolayer hexagonal lattice possessed a linear dispersion relation with a velocity that...
Hello all,
I have read a few papers lately that have used DFT based techniques to investigate metallic adatom adsorption on top of graphene (see for instance PRB 77, 235430 2008). I was under the impression that electrons in graphene are described by the Dirac equation and not the...
Hello all,
We are currently in the middle of a study involving adsorbates on the surface of CNT using vibrational spectroscopy. I don't have much experience with this, but I was wondering if it is possible to predict the peaks using first-principles calculations? If so would anyone be...
Hello all,
I am beginning a study on II-VI semiconductors and I have read numerous theoretical papers that mention the importance of p-d coupling, in particular the need to include the cation d states in the valency in order to accurately predict ground state properties (i.e lattice...
Hello all,
In my research, I use DFT from time to time using SIESTA or VASP. I have spent much time reading up on the various aspects of DFT and think I have a pretty good handle on it. In order to prove this to myself, I would like to start to write my own code. I am however finding that...
Hello all,
I am beginning a new research project involving graphene. Although I have be actively doing a literature search on graphene, I was wondering if somebody would be will to suggest a good textbook that covers the basic of graphene
Thanks in advance
-Ed