Overview#

Mechanism configurations are contained in a single JSON or YAML file.

At the highest level, the configuration file contains information about the name of the mechanism, the version of Mechanism Configuration being used, and the three main components of the mechanism: species, phases, and reactions.

Each of these three sections can be written in one of two formats:

  • Inline — the content is listed directly in the main configuration file (version 1.0.x)

  • File-list — the content is split across one or more separate files referenced by a files key (version 1.1.x)

Both formats can be mixed freely within the same configuration file. For example, species can be inline while reactions references external files.

Note

File-list format requires minor version 1 or greater (e.g. 1.1.0). Inline-only configurations use minor version 0 (e.g. 1.0.0).

Inline format#

All sections are defined directly in the main file. Use version 1.0.0.

version: 1.0.0
name: My Mechanism
species:
  - ...
phases:
  - ...
reactions:
  - ...

{
  "version": "1.0.0",
  "name": "My Mechanism",
  "species": [ "..." ],
  "phases": [ "..." ],
  "reactions": [ "..." ]
}

File-list format#

Each section references one or more external files. The files are resolved relative to the main configuration file. Multiple files are merged in order. Use version 1.1.0.

version: 1.1.0
name: My Mechanism
species:
  files:
    - species.yaml
phases:
  files:
    - gas_phase.yaml
reactions:
  files:
    - troposphere.yaml
    - stratosphere.yaml

{
  "version": "1.1.0",
  "name": "My Mechanism",
  "species": { "files": ["species.json"] },
  "phases":  { "files": ["gas_phase.json"] },
  "reactions": {
    "files": ["troposphere.json", "stratosphere.json"]
  }
}

Mixed format#

Sections can independently use inline or file-list format in the same file. Use version 1.1.0 when any section is a file-list.

{
  "version": "1.1.0",
  "name": "My Mechanism",
  "species": [
    { "name": "A" },
    { "name": "B" }
  ],
  "phases": { "files": ["gas_phase.json"] },
  "reactions": { "files": ["reactions.json"] }
}

The three main components of a mechanism configuration are described here:

Chemical Species

Phases

Reactions