Graphite MBD binding energy - Revision history

Karsai: /* References */

2019-11-14T13:25:26Z

References

← Older revision		Revision as of 13:25, 14 November 2019
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	{{Template:Bulk_systems}}		{{Template:Bulk_systems}}

	~~Back to the [[The_VASP_Manual\|main page]].~~

	[[Category:Examples]]		[[Category:Examples]]

Karsai: /* Download */

2019-11-14T08:39:06Z

Download

← Older revision		Revision as of 08:39, 14 November 2019
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	== Download ==		== Download ==
	[[Media:GraphiteBinding mbd.tgz\| graphiteBinding_mdb.tgz]}		[[Media:GraphiteBinding mbd.tgz\| graphiteBinding_mdb.tgz]]

	== References ==		== References ==

Karsai: /* Download */

2019-11-14T08:38:58Z

Download

← Older revision		Revision as of 08:38, 14 November 2019
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	== Download ==		== Download ==
	[~~http~~:~~//www.vasp.at/vasp-workshop/examples/graphiteBinding_mbd~~.tgz graphiteBinding_mdb.tgz]		[[Media:GraphiteBinding mbd.tgz\| graphiteBinding_mdb.tgz]}

	== References ==		== References ==

Vaspmaster: /* Running this example */

2019-06-24T21:14:32Z

Running this example

← Older revision		Revision as of 21:14, 24 June 2019
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	To run this example, execute the <code>run.sh</code> bash-script:		To run this example, execute the <code>run.sh</code> bash-script:
			<pre>
			#
			# To run VASP this script calls $vasp_std
			# (or posibly $vasp_gam and/or $vasp_ncl).
			# These variables can be defined by sourcing vaspcmd
			. vaspcmd 2> /dev/null

			#
			# When vaspcmd is not available and $vasp_std,
			# $vasp_gam, and/or $vasp_ncl are not set as environment
			# variables, you can specify them here
			[ -z "`echo $vasp_std`" ] && vasp_std="mpirun -np 8 /path-to-your-vasp/vasp_std"
			[ -z "`echo $vasp_gam`" ] && vasp_gam="mpirun -np 8 /path-to-your-vasp/vasp_gam"
			[ -z "`echo $vasp_ncl`" ] && vasp_ncl="mpirun -np 8 /path-to-your-vasp/vasp_ncl"

			#
			# The real work starts here
			#

			# Here the work starts
			rm results.dat

			drct=$(pwd)

			for i in graphene graphite
			do
			cd $drct/$i
			$vasp_std
			done

			cd $drct

			# obtain total energy for graphite
			en2=$(grep "free ene" graphite/OUTCAR \|tail -1\|awk '{print $5}')

			# obtain total energy for graphene
			en1=$(grep "free ene" graphene/OUTCAR \|tail -1\|awk '{print $5}')

			# compute interlayer binding energy (eV/atom)
			deltaE=$(echo print $en2/4 - $en1/2 \|python)

			echo "Binding energy (eV/atom): " $deltaE >results.dat
			</pre>

	Note that the calculation is performed in two steps (two separate single-point calculations) in which the energy for bulk graphite and for graphene are obtained.		Note that the calculation is performed in two steps (two separate single-point calculations) in which the energy for bulk graphite and for graphene are obtained.

Vaspmaster: /* Running this example */

2019-06-24T21:13:35Z

Running this example

← Older revision		Revision as of 21:13, 24 June 2019
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	== Running this example ==		== Running this example ==

	~~Once again~~, the ~~calculation is performed in two steps~~		To run this example, execute the <code>run.sh</code> bash-script:
	~~(single~~-~~point calculations) in which the energy for~~
	~~bulk graphite and for graphene are obtained.~~
	~~The binding energy is computed automatically and it~~
	~~is written in the file results.dat.~~

	The computed value of 0.050 eV/A is now fairly close to		Note that the calculation is performed in two steps (two separate single-point calculations) in which the energy for bulk graphite and for graphene are obtained.
	the RPA reference of 0.048 eV/atom		The binding energy is computed automatically and it is written in the file <code>results.dat</code>.
	<ref name="lebegue"/>.		(N.B.: for the latter ''python'' needs to be available.)

			The computed value of 0.050 eV/A is now fairly close to the RPA reference of 0.048 eV/atom <ref name="lebegue"/>.

	== Download ==		== Download ==

Vaspmaster: /* Task */

2019-06-24T21:10:30Z

Task

← Older revision		Revision as of 21:10, 24 June 2019
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	== Task ==		== Task ==

	~~Determine~~ the interlayer binding energy of graphite in its experimental structure using the MBD@rsSCS method of Tchatchenko ''et al.'' to account for van der Waals interactions.		In this example you will determine the interlayer binding energy of graphite in its experimental structure using the MBD@rsSCS method of Tchatchenko ''et al.'' to account for van der Waals interactions.

			Semilocal DFT at the GGA level underestimates long-range dispersion interactions.
			In the case of graphite, PBE predicts the interlayer binding energy of ~1 meV/atom which is too small compared to the RPA reference of 0.048 eV/atom <ref name="lebegue"/>.
			In contrast, the pairwise correction scheme of Tkatchenko and Scheffler, overestimates this quantity strongly (0.083 eV/atom, see the [[Graphite TS binding energy]] example).
			Here we show that this problem can be eliminated by if many-body effects in dispersion energy are taken into account using the MBD@rsSCS method of Tchatchenko et al. (see [[Many-body dispersion energy]]).

	== Input ==		== Input ==

Vaspmaster: /* Calculation */

2019-06-24T21:07:49Z

Calculation

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-== Calculation ==
+== Running this example ==
 Once again, the calculation is performed in two steps
@@ Line 93: / Line 77: @@
 the RPA reference of 0.048 eV/atom
 <ref name="lebegue"/>.
 == Download ==

Karsai at 13:21, 7 June 2019

2019-06-07T13:21:29Z

← Older revision		Revision as of 13:21, 7 June 2019
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	{{Template:Bulk_systems}}		{{Template:Bulk_systems - Tutorial}}

	== Task ==		== Task ==

Karsai: /* References */

2017-08-10T11:05:30Z

References

← Older revision		Revision as of 11:05, 10 August 2017
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	<ref name="lebegue">[https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.105.196401 S. Lebègue, J. Harl, Tim Gould, J. G. Ángyán, G. Kresse, and J. F. Dobson, Phys. Rev. Lett. 105, 196401 (2010).]</ref>		<ref name="lebegue">[https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.105.196401 S. Lebègue, J. Harl, Tim Gould, J. G. Ángyán, G. Kresse, and J. F. Dobson, Phys. Rev. Lett. 105, 196401 (2010).]</ref>
	</references>		</references>
	~~----~~
	~~[[VASP tutorials\|To the list of examples]] or~~ to the [[The_VASP_Manual\|main page]]		{{Template:Bulk_systems}}

			Back to the [[The_VASP_Manual\|main page]].

	[[Category:Examples]]		[[Category:Examples]]

Karsai: /* References */

2017-07-04T11:09:24Z

References

← Older revision		Revision as of 11:09, 4 July 2017
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	</references>		</references>
	----		----
	[[~~VASP_example_calculations~~\|To the list of examples]] or to the [[The_VASP_Manual\|main page]]		[[VASP tutorials\|To the list of examples]] or to the [[The_VASP_Manual\|main page]]

	[[Category:Examples]]		[[Category:Examples]]