Molecular modeling often involves working with complex structural models. Whether you’re analyzing molecular properties, filtering nodes, or customizing designs, having a clear understanding of a platform’s attribute space is crucial. For users of the SAMSON platform, the structuralModel attribute space offers powerful ways to work with structural models through the Node Specification Language (NSL). In this blog, we’ll dive into practical tips to leverage these structural attributes and simplify your modeling journey.
What is the Structural Model Attribute Space?
The structuralModel attribute space (short name: sm) is designed specifically for nodes that represent structural models. It features attributes that help users query, filter, and analyze structural data efficiently.
Attributes come in two forms: inherited attributes (e.g., visible) from the broader node attribute space, and attributes unique to structuralModel (e.g., numberOfAtoms). Each attribute provides a specific way to match or filter nodes based on their properties.
Key Features and Practical Examples
1. Counting Atoms in Structural Models
One of the most useful attributes, numberOfAtoms, allows users to match structural models with a specific number of atoms. For instance:
sm.nat > 100: Matches models with more than 100 atoms.sm.nat 100:200: Matches models containing between 100 and 200 atoms.
This is particularly useful for tasks like filtering molecular datasets or narrowing down models to a manageable size for further simulation.
2. Filtering by Composition
The attributes numberOfCarbons (sm.nC), numberOfHydrogens (sm.nH), numberOfOxygens (sm.nO), and their counterparts for other elements help users query specific molecular compositions. For example:
sm.nC < 10: Filters models with fewer than 10 carbon atoms.sm.nH 10:20: Matches models with hydrogen atom counts ranging from 10 to 20.
3. Targeting Molecular Structures
With attributes like numberOfMolecules (sm.nm) or numberOfChains (sm.nc), users can isolate molecules exhibiting specific structural configurations. For example:
sm.nc 2:4: Matches models containing 2 to 4 chains.sm.nm < 3: Filters models with fewer than 3 molecules.
These features help users focus on particular structural features without sifting through large datasets manually.
How to Use These Attributes
Leveraging these attributes effectively lies in combining them logically. Consider the following:
- To select molecules with exactly 200 atoms and more than 10 oxygen atoms:
sm.nat 200 and sm.nO > 10. - To identify structural models that are visible on screen and have more than 2 chains:
sm.v and sm.nc > 2.
Why This Matters
For molecular modelers, filtering structural models with accuracy can save hours of manual work. Whether your focus is on proteins, small molecules, or hybrid systems, these attributes provide a precise way to manage structural data. From highlighting key fragments to grouping molecules for further analysis, the possibilities are endless.
Remember, you can learn more about the full range of structural model attributes available in SAMSON by visiting the official documentation page.
SAMSON and all SAMSON Extensions are free for non-commercial use. Get SAMSON today at https://www.samson-connect.net.