Effortlessly Select Atoms with Mathematical Precision

For molecular modelers, one common challenge is efficiently manipulating and selecting specific atoms of a structure to explore modifications, analyze behaviors, or prepare systems for simulations. What if there were a way to harness mathematical expressions to precisely select the atoms you are working with? Look no further! The Atoms Selector Extension in SAMSON delivers this functionality seamlessly, saving significant time and effort.

By leveraging mathematical expressions, you can craft selective operations with unparalleled accuracy. Whether you need to select atoms within a spherical region, isolate a specific chain in a protein, or build complex geometries for your experiments, the Atoms Selector has your back!

How It Works

The Atoms Selector Extension utilizes the same scripting logic as SAMSON’s Simple Script Extension, but with a more specialized focus: it allows users to select atoms based on a mathematical expression. The extension provides access to predefined variables, operators, and functions, making it versatile for both simple queries and more complex condition-based selections.

For instance, a straightforward expression can be crafted to select all atoms within a specific radius from a center:
((a.x-15)^2 + (a.y-15)^2) < 100. This example can be used to carve out a cylindrical shape from a material, such as quartz. The syntactic simplicity combined with powerful logic operators makes this extension incredibly user-friendly for scientific tasks.

Why Use Atoms Selector?

Atom search and manipulation tasks are often tedious without the right tools. Here’s how the Atoms Selector Extension solves some of these common pain points:

Precision: Use variables like a.x, a.y, and a.z for spatial dimensions, or properties like a.element and a.chainID to pinpoint desired atoms.
Time-Saving: Quickly define complex criteria instead of manually selecting atoms or navigating through large molecular systems.
Versatility: Employ logical, mathematical, and algebraic operators for sophisticated calculations and queries, enabling atomic selection customized to your specific research objectives.

Visual Examples

Here’s an illustration of how the Atoms Selector Extension can be applied:

Suppose you want to cut a cylindrical section out of quartz crystal. By using the expression:

((a.x-15)^2 + (a.y-15)^2) &lt; 100

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						((a.x-15)^2 + (a.y-15)^2) &lt; 100

This script selects all atoms within a 10 Å radius from the center point (15, 15) in the x-y plane. The selected region will appear visually in SAMSON as shown:

This method can be adapted to various structures and conditions, offering flexibility for more intricate geometries and workflows.

Key Features at a Glance

Access a wide range of predefined variables like spatial coordinates, atomic properties, and chain IDs for precise queries.
Utilize logical combinations, allowing complex operations (e.g., combining and, or, not conditions).
Include an additional all keyword to select every atom in the active document quickly.

Where to Start

If you’re intrigued by this capability, you can explore more about this extension by visiting the detailed documentation page. This page also covers other powerful tools available in SAMSON for modeling at the atomic level, opening new doors of creativity and experimentation for molecular scientists.

SAMSON and all SAMSON Extensions are free for non-commercial use. Don’t wait—start exploring these unique capabilities by getting SAMSON today at SAMSON Connect.