Psi4 Finite Difference Hessian

Cube to calculate a Hessian using finite-difference of gradients. The expected input is an ensemble of optimized conformers which are used to generate input for gradient calculations. The ‘success’ port should be connected to a Cube to calculate gradients in (Hartrees/Bohr) and then the gradient output is expected to come in through the ‘grad_data’ input port. When the hessian is finished being calculated the results are sent to the ‘hessian_output’ port. This Cube computes DFT Hessian. It uses parallelized finite difference gradient calculations.

Main Parameters

Parameter Name

Extended Log Field

Log Field


Calculation Parameters

  • CPUs (cpu_count) type: integer: The number of CPUs to run this cube with
    Default: 1 , Min: 1, Max: 128
  • Cube Metrics (cube_metrics) type: string: Set of metrics to be collected

    Choices: cpu, disk, memory, network
  • Temporary Disk Space (MiB) (disk_space) type: decimal: The minimum amount of disk space in MiB (1048576 B) this cube requires. Due to overhead, request a couple hundred MiB more than required.
    Default: 5120.0 , Min: 128.0, Max: 8589934592
  • Finite Difference Displacement (epsilon) type: decimal: Finite difference coordinate displacement in Angstrom for Hessian computation.
    Default: 0.01
  • GPUs (gpu_count) type: integer: The number of GPUs to run this cube with
    Default: 0 , Max: 16
  • Instance Tags (instance_tags) type: string: Only run on machines with matching tags (comma separated)
    Default: “”
  • Instance Type (instance_type) type: string: The type of instance that this cube needs to be run on
  • Maximum Initial Gradient (maximum_grad) type: decimal: Hessian calculations require the initial structure to be a local minima. If the maximum gradient is above this threshold then the calculation will fail.
    Default: 0.0001
  • Memory (MiB) (memory_mb) type: decimal: The minimum amount of memory in MiBs (1048576 B) this cube requires. Due to overhead, request a couple hundred MiB more than required.
    Default: 1800 , Min: 256.0, Max: 8589934592
  • Metric Period (metric_period) type: decimal: How often to sample metrics, in seconds
    Default: 60
    Choices: 1, 5, 10, 30, 60, 120, 180, 240, 300, Min: 1, Max: 300
  • Spot policy (spot_policy) type: string: Control cube placement on spot market instances
    Default: Prohibited
    Choices: Allowed, Preferred, NotPreferred, Prohibited, Required

Field parameters

  • Extended Log Field (ext_log_field) type: Field Type: StringVec: Message extended log field
    Default: Extended Log Field
  • Input Molecule Field (in_mol_field) type: Field Type: Chem.Mol: Primary Molecule Field to use as input to the Cube
  • Log Field (log_field) type: Field Type: String: The field to store messages to floe report
    Default: Log Field
  • Output Molecule Field (out_mol_field) type: Field Type: Chem.Mol: Primary Molecule Field to use as output to the Cube
  • Structure index (structure_id_field) type: Field Type: Int: Integer index for labeling incoming structrure ids
    Default: structure id

Hardware Parameters

Machine hardware requirements
  • Memory (MiB) (memory_mb) type: decimal: The minimum amount of memory in MiBs (1048576 B) this cube requires. Due to overhead, request a couple hundred MiB more than required.
    Default: 1800 , Min: 256.0, Max: 8589934592
  • Temporary Disk Space (MiB) (disk_space) type: decimal: The minimum amount of disk space in MiB (1048576 B) this cube requires. Due to overhead, request a couple hundred MiB more than required.
    Default: 5120.0 , Min: 128.0, Max: 8589934592
  • GPUs (gpu_count) type: integer: The number of GPUs to run this cube with
    Default: 0 , Max: 16
  • CPUs (cpu_count) type: integer: The number of CPUs to run this cube with
    Default: 1 , Min: 1, Max: 128
  • Instance Type (instance_type) type: string: The type of instance that this cube needs to be run on
  • Spot policy (spot_policy) type: string: Control cube placement on spot market instances
    Default: Prohibited
    Choices: Allowed, Preferred, NotPreferred, Prohibited, Required
  • Instance Tags (instance_tags) type: string: Only run on machines with matching tags (comma separated)
    Default: “”

Metrics Parameters

Cube Metric Parameters
  • Metric Period (None) type: decimal: How often to sample metrics, in seconds
    Default: 60
    Choices: 1, 5, 10, 30, 60, 120, 180, 240, 300, Min: 1, Max: 300
  • Cube Metrics (None) type: string: Set of metrics to be collected

    Choices: cpu, disk, memory, network