Dynamics_Velocity_Verlet contains a procedure for performing a molecular dynamics simulation with a velocity Verlet algorithm.
The basic ideas of molecular dynamics simulations are described in chapters 8 and 10 of the book A Practical Introduction to the Simulation of Molecular Systems. The basic concepts of using the DYNAMO library for dynamics calculations remain the same as described there although there has been a slight rearrangement of the dynamics modules since the book was completed.
Module | Variables |
---|---|
DEFINITIONS | DP |
IO_UNITS | OUTPUT |
STATUS | ERROR |
ATOMS | ATMCRD, ATMFIX, NATOMS, NFREE |
DYNAMICS_UTILITIES | Most of the public items in the module. |
VELOCITY | ATMVEL, EKE, TEMPERATURE, VELOCITY_SCALE, VELOCITY_TEMPERATURE |
None.
There is a single public subroutine in this module.
Subroutine | Purpose |
---|---|
VELOCITY_VERLET_DYNAMICS | Perform a molecular dynamics simulation using a velocity Verlet algorithm. |
Argument | Type | Intent | Optional | Purpose |
---|---|---|---|---|
TARGET_TEMPERATURE | Real | In | Yes | The target temperature for the simulation. |
SCALE_FREQUENCY | Integer | In | Yes | The step frequency for velocity scaling. |
SCALE_OPTION | Character ( Len = * ) | In | Yes | The scale option. |
Error | Meaning |
---|---|
No velocities exist. | No velocities have been assigned. |
Final temperature not specified for scaling options. | The SCALE_OPTION "EXPONENTIAL" or "LINEAR" was specified but the argument TARGET_TEMPERATURE was absent. |
Invalid SCALE OPTION. | The argument SCALE_OPTION is not one of the strings "CONSTANT", "EXPONENTIAL" or "LINEAR". |
Stable.