Format of sannp.metro

Executing sannp --metro-temp outputs the template of sannp.metro.

A Line that initial character is # or ! is dealt with as a comment.

SWAPPING and GEOMETRY indicate the beginning of each section, and the next and subsequent lines are the contents of the section. GEOMETRY is mandatory.

maxSteps

Specify the number of steps of Monte Carlo calculations.

numGeoms

Specify the number of structures to generate. Calculation stops after generating as many structures as this value.

unknownGeoms

Allow only unknown structures to be output. It is used at reinforcement learning. Referring to the distribution of symmetry functions generated at NNP learning (sannp.gdist), determine unknown in case that there are insufficient number of structures which have close values of symmetry functions.

temperature

Specify the temperature (K) of the Boltzmann factor in the Metropolis method.

upperEnergy

Specify the upper limit of energy (eV/atom). Structures with larger energy than this value is not transferred.

lowerEnergy

Specify the lower limit of energy (eV/atom). Structures with smaller energy than this value is not transferred.

withShift

Specify using displacement of atoms (1) or not (0) as transition processes in the Metropolis method.

shiftCoord

Specify displacement distance (Å) of an atom.

shiftInit

Specify randomly displacing all of the atoms (1) or not (0) before initiating calculation.

shiftCoordInit

Specify displacement distance (Å) of an atom before initiating calculation.

SWAPPING

Set up replacements of atoms as transition processes.

Specify the number of replacement pairs in the 1st line and replacement pair with element names after the 2nd line. Using X as an element name express a vacancy. The same element name is unavailable as a pair.

Temperature of a pair can be individually set up by specifying temperature (K) after the pair. If temperature is omitted or specified as 0 or lower value, the temperature specified with keyword temperature is used.

Without a SWAPPING section, replacements of atoms is not used as transition processes.

Example

3
Si C
Si X
Si O 300.0

GEOMETRY

Set up the initial structure.

Specify the number of atoms in the 1st line, lattice vectors in the 2nd-4th lines, and element names / atomic coordinates (Å) in and after the 5th line. Using X as an element name express a vacancy. An atom is fixed if fix is put after an atomic coordinate.

Example

108
12.11678900   0.00000000   0.00000000
 0.00000000  12.11678900   0.00000000
 0.00000000   0.00000000  12.11678900
X        0.222057  -0.330325  -0.114595
Al       0.003512   1.943050   2.047290
Al       2.050750  -0.070341   1.960020
Al       1.912160   2.024660  -0.301394 fix
...