mirror of https://github.com/abinit/abinit.git
80 lines
3.4 KiB
Plaintext
80 lines
3.4 KiB
Plaintext
#Driver
|
|
|
|
atom 1 # The basin of attraction of Oxygen atom will be examined
|
|
crit 2 # determine the critical points
|
|
surf 1 # build the Bader surface
|
|
gpsurf 1 # output for GNUplot
|
|
irho 1 # drives the integration of the Bader charge
|
|
|
|
#Parameter
|
|
|
|
# nsa 2 # one might gain a bit of cpu time
|
|
# nsb 2 # by using these values, smaller than the default
|
|
# nsc 2
|
|
|
|
inpt 50 # This value is suitable
|
|
ntheta 8 # This value is much too small
|
|
nphi 4 # This value is much too small
|
|
thetamax 3.14159265358 # These two variables define a quadrant
|
|
phimax 1.57079632679 #
|
|
maxatd 10.9 # The starting atoms within this distance are sufficient
|
|
maxcpd 8.0
|
|
lgrad2 1.0d-4 # Such loose criteria are needed to catch all the CPs.
|
|
lstep2 1.0d-4 #
|
|
dpclim 5.0d-2 # Because the ecut is quite low, the finite elements
|
|
# are quite large. So, it might be that ONE critical point
|
|
# is seen on TWO finite elements, while being at a larger
|
|
# distance that the default value of dpclim
|
|
|
|
#%%<BEGIN TEST_INFO>
|
|
#%% [setup]
|
|
#%% executable = aim
|
|
#%% exclude_builders = ubu_intel_16.0_openmp, bob_gnu_13.2_openmp
|
|
#%% test_chain = t32.abi, t33.abi, t34.abi
|
|
#%% [files]
|
|
#%% files_to_test =
|
|
#%% t33.out, tolnlines = 19, tolabs = 2.000e-03, tolrel = 2.000e-04, fld_options = -medium
|
|
#%% psp_files = DensityCore_pw/08-O.8.fc, DensityCore_pw/12-Mg.8.fc
|
|
#%% [paral_info]
|
|
#%% max_nprocs = 1
|
|
#%% [extra_info]
|
|
#%% authors = Unknown
|
|
#%% keywords =
|
|
#%% description =
|
|
#%% MgO molecule, Bader analysis.
|
|
#%% Examine the Oxygen atom only.
|
|
#%% Determine 2 bonding critical points (only !),
|
|
#%% 8 ring critical points, and 8 cage critical points.
|
|
#%% (In agreement with Euler's relation : #BCP-#RCP+#CCP=2)
|
|
#%% The ecut that was used in test case 32 is quite
|
|
#%% low, so that the accuracy of the critical points is not
|
|
#%% too good. Especially, symmetries are broken at the level
|
|
#%% of 0.0003.
|
|
#%% Get 2 core electrons, 6.8043 valence electrons.
|
|
#%% The nucleus charge is +8. The Oxygen atom-in-molecule
|
|
#%% has a net charge of -0.8043.
|
|
#%% Additional explanation about the weak number of BCP
|
|
#%% for oxygen. One might expect the O atom to be connected
|
|
#%% through the other O atoms in neighbouring cells (x and y
|
|
#%% directions - hence 4 BCPs in these directions), but
|
|
#%% one sees that the only existing BCPs
|
|
#%% are towards the Mg atoms. This is surprising, but correct ! Indeed,
|
|
#%% the density at the middle of the segment between two O atoms
|
|
#%% along x (or y) is LOWER than the density at the
|
|
#%% middle of the segment between two Mg atoms along x (or y).
|
|
#%% Indeed, although the O atoms attract electrons from the Mg
|
|
#%% atoms, they become negatively charged, and the potential,
|
|
#%% in DISTANT regions of the molecule, is lower (so more
|
|
#%% attractive) on the side
|
|
#%% of the Mg atoms than on the side of the O atoms !
|
|
#%% This means that the tail of the density extends further
|
|
#%% in the x-y plane containing the Mg atoms, than in the
|
|
#%% x-y plane containing the O atoms. So, the middle of the
|
|
#%% segment connecting the O atoms actually belongs to the
|
|
#%% Mg basin of attraction, and is close to a Cage Critical Point
|
|
#%% shared by Oxygen and Magnesium atoms. By contrast, the
|
|
#%% middle of the segment connecting the Mg atoms is, as expected,
|
|
#%% close to a Bond Critical Point.
|
|
#%% topics = Bader
|
|
#%%<END TEST_INFO>
|