What's the difference between free Mercury and full-licence Mercury?

The CCDC offers a selection of products and services free of charge for the benefit of the scientific community, which includes a free version of Mercury. While the free version supports several functionalities, many popular features are only available with a licence. Here we explain the differences between the free and paid licence versions of Mercury.

What is Mercury?

Mercury is our crystal structure visualisation, exploration and analysis software. It offers a comprehensive range of tools for 3D structure visualization and the exploration of crystal packing. It uses the unique data in the Cambridge Structural Database (CSD) as a knowledge base to help with molecular and crystallographic problems, like identifying likely molecular conformations and intermolecular interaction modes. Mercury also allows you to generate conformers based on geometrical statistics from the CSD.

Licensed versions of Mercury are available in all of CCDC’s software suites, including CSD-Core, CSD-Discovery and CSD-Materials. While these licences unlock different feature sets within Mercury to best support different application areas, CSD-Enterprise licences – including those for universities and academics – include all available Mercury features. The free version of Mercury through CSD-Community offers an abridged list of functionalities and access to a teaching subset of the CSD.

This table quickly summarizes which features are included with which licences.

Who can use free Mercury?

The free version of Mercury is available to everybody as part of CSD-Community, and it is meant to support non-commercial, structural science research. Users are permitted to download and use a single copy of the program and accompanying documentation solely for internal research, development or teaching purposes.

What can you do in the free version of Mercury?

The free (or CSD-Community) version of Mercury supports exploring crystal structures, customising display settings and generating publication-quality images. For example, with the free version of Mercury you can:

  • Open chemical & structural files including MOL2, CIF, RES, PDB and other formats (see the full list here).

  • Crystal packing
  • View chemical structures in 3D, customise their appearance, display symmetry and other features.

  • Explore crystallographic structures through their longer-range interactions such as hydrogen bonds, short contacts and polymeric expansion.

  • Access the CSD Teaching Subset to explore and understand key concepts in chemistry.

  • Create high-resolution images of structures for publications, lab reports, or presentations (see how to reference Mercury here).

  • Generate a file to 3D print molecular & crystallographic structures.

  • Simulate PXRD patterns.

What functionalities are not available in the free version of Mercury?

The following tools are only available through a paid licence version of Mercury:

  • Molecule and structure editing

  • Display of voids and hydrogen-bond graph sets

  • Plotting, charting and reporting structural data

  • Descriptive statistics on structural data

  • Conformation analysis, including bond length, valence angle, torsion angle and ring geometry assessment

  • Conformer generation

  • Ligand-based drug discovery features, like ligand overlay, field-based ligand screener

  • Solid-form analysis features, like motif searching, packing feature searching, calculations, hydrogen bond propensity and coordination, full interaction maps, hydrate or solvate analysis, aromatic analysis and co-crystal design

What are some examples of what you can do with the licence-only functionalities?

The free version of Mercury only offers access to 750+ structures in our teaching database, which are selected to demonstrate key chemistry concepts for learning and teaching. The CSD houses over 1.1 million structures which are all available in the full licence version of Mercury.

We also recommend you edit the structures and assign bonds when you first open structures through Mercury; however, that functionality is only available with a paid licence. And while the free version supports most display options, you can’t display voids, which is one of the most popular features in the licenced versions.

Below are additional examples of popular functionalities only available through a CSD-Core, CSD-Discovery, CSD-Materials or CSD-Enterprise licence.

Overlaying Molecules

This tool enables you to see how two molecules within the same structure differ. For example, if you have a multi-molecule structure (Z'>1), and you’re having a hard time seeing both structures – potentially because the two molecules look so similar – this tool can help. It overlaps two molecules from the same asymmetric unit cell to compare conformations. It will also provide symmetry information that may highlight a property of interest, like whether there is an inversion centre.

Structure Overlay

You can also overlay molecules that are not in the same structure. This can be helpful to visualise the effects of a solvate – for example, to see if it is causing a geometric rearrangement in a pharmaceutical ingredient or another molecule of interest.

Display Bravais, Friedel, Donnay and Harker (BFDH) Crystal Morphology

This tool calculates the crystal morphology based on the unit cell and predicts how molecules are arranged within the crystal. You can select to fill the BFDH crystal with those molecules with molecular centroids within all BFDH facets. This can help you understand and control growth morphology – for example, it can show you which structures might inhibit crystal growth. It can also be helpful to see which functional groups are exposed on each facet of the crystal.

Read about more tools in Mercury and their applications here.

How can I get a Mercury licence?

There are a few options, and we’d love to help you find the right licence for your purposes. To get more information, contact us here.

Or, if you don’t need all functions, for internal research, development or teaching download the free version of Mercury through CSD-Community here.