SCM Calculators in ASE¶
ASE calculators are implemented for ADF, BAND, DFTB and ReaxFF.
The options for the programs in the Amsterdam Modeling Suite are controlled by a single string containing all the information required to set up the respective calculations with AMSprep.
Technical Notes¶
New Interface Design in ADF2017¶
ADF2017 ships new, simplified versions of all calculator interfaces to ASE. The interfaces for setting up these new classes are not compatible to those in earlier versions of the Amsterdam Modeling Suite, but support now all calculation options accepted by AMSprep. Examples on the usage of the new classes are shown below.
Interfaces to Individual Programs¶
The ASE calculators for the programs of the Amsterdam Modeling Suite derive from a common parent class (basically an interface to AMSprep and AMSreport) and differ from each other only in some program-specific filename internals. All of SCM’s ASE interfaces can therefore be constructed in the following fashion
myCalculator = CalculatorName(label, amsprep_options, ...)
where CalculatorName can be any of the following:
| ADF: | ADFCalculator |
|---|---|
| BAND: | BANDCalculator |
| DFTB: | DFTBCalculator |
| ReaxFF: | ReaxFFCalculator |
Usage and Examples¶
Import¶
Within the ASE repository, the SCM calculator classes are all implemented in calculators/scm.py and can be imported via
from ase.calculators.scm import ADFCalculator
Interface Keywords¶
The constructors of the SCM’s calculator classes include the following keywords
label: | (default: label=None) calculation tag used for calculation directory and prefix for calculation files: label='dir1/abc' will create a directory dir1 and name the calculation files therein as abc.XXX while label=abc will use the current directory and create calculation files as abc.XXX in it during runtime. |
|---|---|
amsprep_options: | |
(default: amsprep_options=None) string containing a sequence of options accepted by AMSprep.
Please consult the AMSprep manual for further details.
Also note that the calculator will explicitly add the options -j calculationFile, -sym NOSYM, -importangstrom, and -gradientsonly to the option list before invoking the amsprep command. |
|
Examples¶
Single point energy and gradients calculation with ADF
from ase.io.scmio import *
from ase.calculators.scm import *
myAtoms = read_scmxyz('myAtoms.xyz')
myCalculator = ADFCalculator(label='myCalculation', amsprep_options='-t ADF-EG')
myAtoms.set_calculator(myCalculator)
print(myAtoms.get_potential_energy())