Guide to KIM IDs

KIM IDs are permanent identifiers for content stored in the KIM Repository. These identifiers can be cited in publications.

KIM IDs have the format:



CC is a two-letter alphabetical code:

  • MO – Model
  • MD – Model Driver
  • TE – Test
  • TD – Test Driver
  • RD – Reference Data
  • VZ – Visualizer
  • MV – Model Verification
  • TV – Test Verification
  • VV – Visualizer Verification

DDDDDDDDDDDD is a 12-digit randomly assigned integer code.

VVV is a 3-digit version number starting at 000.

Extended KIM IDs

To enhance human readability an "Extended KIM ID" is a KIM ID with a prefix describing the item. This prefix is limited to 100 characters maximum, and only alpha-numeric characters (including underscore).

Extended KIM IDs for Models and Model Drivers

The recommended format of the prefix for Models and Model Drivers are:

Model Driver<model type/name>
Model<model type/name>_<developer name(s)>_<model info>_<supported element(s)>

<model type/name>
A brief characterization of the model type. For example, it can be "Pair", "Three_body", "EAM", etc. along with additional identifying information.

<developer name(s)>
The names of the people who developed the model in camel case (e.g. "StillingerWeber").

<model info>
This includes additional information distinguishing the model if needed.

<supported element(s)>
The list of supported elements in camel case (e.g. "AlNi").

By convention, model parameterizations begin with their associated model driver prefix. For example the EAM driver and an associated parameterization are:

  • EAM_Dynamo__MD_120291908751_000
  • EAM_Dynamo_Ercolessi_Adams_Al__MO_123629422045_000

Extended KIM IDs for Tests and Test Drivers

The recommended format of the prefix for Tests and Test Drivers are:

Test Driver<test type/name>
Test<test type/name>_<test info>_<supported element(s)>

<test type/name>
A short description of the test, e.g. "ElasticConstantsCubic" indicates that this test computes the elastic constants of a cubic crystal.

<test info>
This includes additional information distinguishing the model if needed, e.g. "fcc" indicates that the "ElasticConstantsCubic" test is for an fcc crystal.

<supported element(s)>
The list of supported elements in camel case (e.g. "AlNi").

By convention, Tests associated with a Test Driver begin with their associated Test Driver prefix. For example the ElasticConstantsCubic driver and an associated Test are:

  • ElasticConstantsCubic__TD_011862047401_000
  • ElasticConstantsCubic_fcc_Al__TE_944469580177_000

KIM IDs Reserved for Development

The system is responsible for assigning the unique 12-digit integer code that makes up the middle part of an item's KIM ID. However, the OpenKIM Virtual Machine, pipeline, and their associated tools expect item's to have KIM IDs conforming to the format described above. Thus, if you would like to develop new Models, Model Drivers, Tests, and/or Test Drivers, your development code will need to conform to this format.

A special set of 12-digit numbers has been reserved for development use only:


For example, a development Model might have the extended KIM ID:

  • MySuperNewModelOfEverything__MO_000000000001_000

Developer's may take advantage of the 3-digit version numbering to label different version of their development codes:

  • MySuperNewModelOfEverything_RSElliott_AllElements__MO_000000000001_000
  • MySuperNewModelOfEverything_RSElliott_AllElements__MO_000000000001_001
  • MySuperNewModelOfEverything_RSElliott_AllElements__MO_000000000001_010

All new items submitted to the OpenKIM system must conform to this development numbering range.