Last Modified 19 July 1999

STATIC: 1999 Workshop

These are the notes for the DoD CCM workshop which was held at the HEAT Center in Churchville, MD, 19-23 July 1999.

These notes are also available in gzipped Postscript format.

static

A Tight-Binding Program for Total Energy and Electronic Band Structure Evaluation

Developed as part of the Common HPC Software Support Initiative (CHSSI)

by

Michael J. Mehl (mehl@dave.nrl.navy.mil (Privacy Advisory))
and
Dimitrios A. Papaconstantopoulos (papacon@dave.nrl.navy.mil (Privacy Advisory))
Center for Computational Materials Science
Naval Research Laboratory Washington DC, 20375-5345

Acknowledgments:

Dr. R. Cohen, Geophysical Laboratory
Dr. C. Ethridge
Dr. S. Yang, (NRC Postdoc)
Dr. N. Bernstein, NRL (NRC Postdoc)
Prof. S. Richardson, Howard University
Dr. J. Lill, NRL
B. Akdim, George Mason University

Useful Links

DoD Tight-Binding Home Page: http://cst-www.nrl.navy.mil/bind/dodtb
Tight-Binding Parameters: http://cst-www.nrl.navy.mil/bind
Online Registration for static and the fitting code: http://www.arl.hpc.mil/PET/cta/ccm/software/forms/tbmdreg.html
static Source Code (password required): http://cst-www.nrl.navy.mil/users/mehl/static/vers110
Scripts and Auxillary programs (password required): http://cst-www.nrl.navy.mil/users/mehl/static/scripts
static Manual http://cst-www.nrl.navy.mil/bind/static
static Examples http://cst-www.nrl.navy.mil/bind/static/usage.html#examples
Lattice Information http://cst-www.nrl.navy.mil/lattice
CSTB preprint/reprint Archives: http://cst-www.nrl.navy.mil/papers.html
NRL Tight-Binding Papers: http://cst-www.nrl.navy.mil/bind/notes.html#reference
These notes:
http://cst-www.nrl.navy.mil/bind/static/wrkshp99/notes.ps.gz
or
http://cst-www.nrl.navy.mil/bind/static/wrkshp99/notes.html
Bug Reports:
Send to mehl@dave.nrl.navy.mil (Privacy Advisory)
View at http://cst-www.nrl.navy.mil/users/mehl/alpha/static.str.html

static

Determines structure of crystal, including neighbors out to the cutoff radius
Evaluates on-site, Hamiltonian, and Overlap Slater-Koster integrals in two-center approximation
Sets up integration mesh in the Brillouin zone using symmetry information and your desired accuracy
Determines eigenvalues e_n (k_i) for each point k_i on the integration mesh
Determines the total energy of the system by
Optionally (Mode=2,4) determines pressure on the crystal
Optionally (Mode=6,8) determines angular momentum/atomic decomposition of eigenstates
Pre-defined lattice types: fcc, hcp, bcc, etc. Input lattice constants, or volume and c/a ratios. See http://cst-www.nrl.navy.mil/bind/static/lattypes.html
Pre-defined strain types: Useful for calculating elastic constants. See http://cst-www.nrl.navy.mil/bind/static/straintype.html
Many examples available online: http://cst-www.nrl.navy.mil/bind/static/usage.html#examples

New Features in static

Allows use (Mode=1,2) of Gillan's Extrapolation to T=0.
- J. Gillan, J. Phys.: Condens. Matter 1, 689 (1989).
- O. Grotheer and M. Fahnle, Phys. Rev. B 58, 13459 (1998).
New scripting utility, skingen, to set up SKIN files.
New scripting utility, plotdos, to plot electronic Density of States (DOS) and band structure for simple crystals: fcc, bcc, and simple cubic.

Useful Programs

These programs make it a lot easier to run static and to visually interpret the results. It should be possible to compile and run these codes on almost any machine which runs X11. All programs are Open Source. See http://cst-www.nrl.navy.mil/bind/static/appendix.html#useful for more details.

Perl -- http://www.perl.org/
gnuplot -- http://www.geocities.com/SiliconValley/Foothills/6647/ Version 3.7 or higher is recommended.
ghostscript and ghostview -- http://www.cs.wisc.edu/~ghost/

Example -- Equation of State of FCC Palladium

For more detail, see

http://cst-www.nrl.navy.mil/bind/static/example1/ for the basic program
http://cst-www.nrl.navy.mil/bind/static/example14/examplea/ for instructions on using skingen

First get the Palladium Parameters
- Go to http://cst-www.nrl.navy.mil/bind/
- Click on ``Pd''
- Choose the parameters $R_{cut} = 10.5$~Bohr and save as pd_par in your working directory

Run skingen to construct the SKINfile:

$ skingen <cr>

Welcome to the NRL SKIN file generator

Enter the mode you want to use (1-9, h for help):  4 <cr>

What kind of calculation do you want to do?

Using mode 4

Enter the Fermi temperature for the electron states:
(>=0, h==help):    0.005 <cr>

TFermi = 0.005
Mode = 3

Enter the eigenvalue cutoff energy (>=0, default = 100, h==help):
 0.500 <cr>

Cutoff temperature is 0.500 Ry

Where are the parameters?

Enter the path to the tight-binding parameterization file:
 pd_par <cr>

Structure 1

Enter the long label for structure 1.

The default is ' ':  Palladium FCC (A1) <cr>

Enter the short (20 character) label
(Default ' '):  fcc  6.80 <cr>

Choose a lattice (1=fcc)

Enter the lattice type (-13,...,13,h=help):  1 <cr>
Lattice type 1

Enter the lattice constant a
(Default ' '):  6.80 <cr>

Enter the strain type [0=none, h=help]:  0 <cr>

How far should we search for neighbors along each primitive lattice
vector? (default = "4 4 4")   <cr>

Atomic Positions

How many atoms in this structure (Default 1)?    <cr>

Note that pressing ``Enter'' accepts the default values

Enter atomic positions in
(1) lattice (default) or (2) Cartesian coordinates: <cr>
The atomic positions will be in lattice coordinates

Enter the index number of atom 1 (Default 1):   <cr>

Enter the atomic position in lattice coordinates, separated by spaces (Default:
        '0.000  0.000  0.000':)  <cr>

Space Group and k-points

Select a space group:
(0=general,1=fcc/bcc/sc/diamond,2=hcp/hexagonal/graphite,3=path,h=help): 1 <cr>

Finally, choose a k-point set for this calculation:
(1) predefined, available for some structures
(2) your own premade k-point file
(3) let the program create a mesh
(h) help (default)
Your choice?   1 <cr>

Pre-defined k-points are available for
(1) fcc/diamond, (2) bcc, (3) sc, (4) hexagonal/hcp lattices.
Please pick one:   1 <cr>

total 119
-r--r--r--  48 mehl     bind           28 Oct 28  1994 regular.00
-r--r--r--  14 mehl     bind          729 May 30  1996 regular.04
-r--r--r--  12 mehl     bind         3532 Sep 24  1996 regular.06
-r--r--r--  16 mehl     bind         3468 Jun  1  1995 regular.08
-r--r--r--  13 mehl     bind         4350 Mar 29  1996 regular.10
-r--r--r--  14 mehl     bind        18090 Jul  2  1996 regular.12
-r--r--r--  12 mehl     bind        26494 Nov 23  1993 regular.14
-r--r--r--  13 mehl     bind        10003 Jul 28  1997 spcgrp.fcc

Your choice?  regular.08 <cr>

New Structure

To add another structure, continue answering questions as before.
To exit, hit ^D at the next prompt.

Note the new default values

Enter the long label for structure 2.
The default is 'Palladium FCC (A1)':   <cr>
Enter the short (20 character) label
(Default ' fcc  6.80'):  fcc  6.90 <cr>

You can't change lattice type, space group, or k-point mesh within skingen

Enter the lattice constant a
(Default '6.80'):  6.90 <cr>

Enter the index number of atom 1 (Default 1): }  <cr>

Enter the atomic position in lattice coordinates, separated by spaces (Default:
    '0.000  0.000  0.000':)    <cr>

To add another structure, continue answering questions as before.
To exit, hit ^D at the next prompt.
Enter the long label for structure 3.
The default is 'Palladium FCC (A1)':

Continue as necessary. At some point you may wish to get out of skingen and edit {\tt SKIN} by hand.
Compare your results with the completed SKIN file at http://cst-www.nrl.navy.mil/bind/static/example14/examplea/SKIN
Run the static code

Your SKENG output should look like this:


 Label       Volume        Fermi Level      Energy        Pressure

 fcc  6.80   78.608000     .256797277     .038518611     .004624940
 fcc  6.90   82.127250     .242276268     .024020018     .003607059
 fcc  7.00   85.750000     .228826554     .012851841     .002567833
 fcc  7.10   89.477750     .216099374     .005144880     .001585545
 fcc  7.20   93.312000     .203907640     .000802042     .000703127
 fcc  7.30   97.254250     .192381931    -.000433135    -.000048809
 fcc  7.40  101.306000     .181915501     .001011535    -.000625782
 fcc  7.50  105.468750     .172358630     .004490358    -.001055989
 fcc  7.60  109.744000     .163145676     .009793201    -.001410457

Plot with gnuplot. See http://cst-www.nrl.navy.mil/bind/static/example1/page3.html for one way to do this.

skingen Notes

skingen can only do one lattice type per file. That is, we can't mix fcc and bcc structures in the same SKIN file.
skingen is very much in the Alpha stage of development. Perl programmers are welcome to modify the source code.
For further adventures with skingen see http://cst-www.nrl.navy.mil/bind/static/example14/exampleb/

The DOS of Silver using plotdos

Note: This is how it should go. Results will vary depending upon your version of Perl and gnuplot.
See http://cst-www.nrl.navy.mil/bind/static/example12/ for more details.

Log onto a HEAT workstation, or install the files in http://cst-www.nrl.navy.mil/users/mehl/static/scripts/ (password required)
At HEAT, make sure that /users/mehl/tb/bin is in your path.
Go to http://cst-www.nrl.navy.mil/bind/ to get the silver parameters.

Click on ``Ag'', and then on ``Get the parameters (ag_par)''. Save them as ag_par in your working directory.

Run plotdos:
$ plotdos <cr> Do you wish to plot the density of states of (1) an fcc crystal, (2) a bcc crystal, or (3) a simple cubic crystal?1 <cr> Enter the path to your tight-binding parameter file:} ag\_par <cr> Enter the cubic lattice constant in Angstroms 4.09 <cr> Setting up the lattice at a = 4.09 Angstroms = 7.7289792932878 Bohr Now running the static program to generate the QLMT file Output of SKENG: 4.09 Angstroms 115.426743 .312795281 .001946354 11 electrons in the calculation Running the tetrahedron program Fermi energy = .31777 Setting up the plot gnuplot script saved as dosplot.gnu Postscript copy of plot is in dosplot.ps
A picture should now appear on your screen:

Plotting the band structure
Do you wish to plot the band structure? (y/n)y <cr> To plot the band structure, we need to move certain files from the density of states (DOS) calculations. Therefore, these DOS specific files have been renamed: SKIN --> SKIN.dos SKOUT --> SKOUT.dos SKENG --> SKENG.dos QLMT --> QLMT.dos Running the static code to produce a new QLMT file Now using gnuplot to create a postscript file: The gnuplot plotting file is available in bands.gnu A postscript picture of the bands is in bands.ps
Another picture should now appear on your screen:
Thank you for using plotdos

About plotdos

plotdos can be rather easily extended to cover certain two-atom unit cells, e.g. diamond, NaCl, or CsCl.
plotdos uses the tetrahedron program to determine the DOS. This is an old program, and not easily extended to an arbitrary lattice.
The program qdos.f, included with plotdos, can calculate a smoothed out DOS for an arbitrary lattice. Eventually we will update plotdos to use qdos.f when necessary.
Others are welcome to do this before we get to it.

In Closing

We welcome

Suggestions
Corrections
Bug Reports
Comments
Questions

We tolerate

``Constructive'' Criticism

Send email to mehl@dave.nrl.navy.mil (Privacy Advisory)

Last Modified 19 July 1999

STATIC: 1999 Workshop

static

A Tight-Binding Program for Total Energy and Electronic Band Structure Evaluation

Developed as part of the Common HPC Software Support Initiative (CHSSI)

by

Michael J. Mehl (mehl@dave.nrl.navy.mil (Privacy Advisory)) and Dimitrios A. Papaconstantopoulos (papacon@dave.nrl.navy.mil (Privacy Advisory)) Center for Computational Materials Science Naval Research Laboratory Washington DC, 20375-5345

Useful Links

static

New Features in static

Useful Programs

Example -- Equation of State of FCC Palladium

What kind of calculation do you want to do?

Where are the parameters?

Structure 1

Choose a lattice (1=fcc)

Atomic Positions

Note that pressing ``Enter'' accepts the default values

Space Group and k-points

New Structure

Note the new default values

You can't change lattice type, space group, or k-point mesh within skingen

skingen Notes

The DOS of Silver using plotdos

A picture should now appear on your screen:

Plotting the band structure

Another picture should now appear on your screen:

About plotdos

In Closing

Michael J. Mehl (mehl@dave.nrl.navy.mil (Privacy Advisory))
and
Dimitrios A. Papaconstantopoulos (papacon@dave.nrl.navy.mil (Privacy Advisory))
Center for Computational Materials Science
Naval Research Laboratory Washington DC, 20375-5345