### Packmol Input Configuration Example

Source: https://context7.com/m3g/packmol/llms.txt

This is a basic example of a Packmol input configuration file. It specifies the output file type, tolerance, and defines a structure block for packing water molecules into a cubic box.

```plaintext
tolerance 2.0
filetype xyz
output output.xyz

structure water.xyz
  number 10
  inside box 0. 0. 0. 20. 20. 20.
end structure
```

--------------------------------

### Install Packmol using pip

Source: https://github.com/m3g/packmol/blob/master/README.md

Installs the Packmol package from the Python Package Index. This is a convenient method for users who prefer using Python environments and provides pre-built wheels for most platforms.

```bash
pip install packmol
```

--------------------------------

### Install Packmol Executable

Source: https://github.com/m3g/packmol/blob/master/CMakeLists.txt

This CMake command specifies that the built 'packmol' executable should be installed into the 'bin' directory. This makes the executable accessible in the system's PATH after installation.

```cmake
install(TARGETS packmol DESTINATION bin)
```

--------------------------------

### Run Packmol directly with uvx

Source: https://context7.com/m3g/packmol/llms.txt

Executes Packmol directly using the 'uvx' command without a formal installation. This is useful for quick testing or running from a temporary environment.

```bash
uvx packmol < input.inp
```

--------------------------------

### Packmol Input for Binary Mixture

Source: https://context7.com/m3g/packmol/llms.txt

Creates a binary mixture of water and urea molecules within a cubic box using Packmol. This example shows how to define multiple structure blocks for different molecule types.

```packmol
# Water-urea mixture
tolerance 2.0
filetype pdb
output output.pdb

structure water.pdb
  number 1000
  inside box 0. 0. 0. 40. 40. 40.
end structure

structure urea.pdb
  number 400
  inside box 0. 0. 0. 40. 40. 40.
end structure
```

--------------------------------

### Packmol Input for Spherical Vesicle

Source: https://context7.com/m3g/packmol/llms.txt

Creates a double-layered vesicle with water inside and outside using spherical constraints in Packmol. This example demonstrates complex spatial arrangements using 'inside sphere' and 'outside sphere'.

```packmol
# Double-layered vesicle
tolerance 2.0

structure palmitoil.pdb
  resnumbers 2
  number 20
  atoms 37
    inside sphere 0. 0. 0. 14.
  end atoms
  atoms 5
    outside sphere 0. 0. 0. 26.
  end atoms
end structure

structure palmitoil.pdb
  resnumbers 2
  number 30
  atoms 5
    inside sphere 0. 0. 0. 29.
  end atoms
  atoms 37
    outside sphere 0. 0. 0. 41.
  end atoms
end structure

structure water.pdb
   resnumbers 2
   number 50
   inside sphere 0. 0. 0. 13.
end structure

structure water.pdb
   resnumbers 2
   number 100
   inside box -47.5 -47.5 -47.5 47.5 47.5 47.5
   outside sphere 0. 0. 0. 43.
end structure

output output.pdb
```

--------------------------------

### Run Packmol from Command Line

Source: https://context7.com/m3g/packmol/llms.txt

Demonstrates two ways to run Packmol from the command line: redirecting input from a file and specifying input and output files as arguments.

```bash
# Run packmol with input file
packmol < input.inp

# Run with explicit input and output file arguments
packmol -i input.inp -o output.pdb
```

--------------------------------

### Compile Packmol using make

Source: https://github.com/m3g/packmol/blob/master/README.md

Compiles the Packmol package from source code using the 'make' utility. This method requires downloading the source tarball or zip file and assumes a Fortran compiler like 'gfortran' is available.

```bash
tar -xzvf packmol-21.0.0.tar.gz
unzip -xzvf packmol-21.0.0.zip
cd packmol
./configure [optional: path to fortran compiler]
make
```

--------------------------------

### Run Packmol using uvx CLI

Source: https://github.com/m3g/packmol/blob/master/README.md

Executes the Packmol command-line interface using uvx, a tool for running CLI applications. This allows direct execution of Packmol with input redirection from a file.

```bash
uvx packmol < inp.pack
```

--------------------------------

### Compile Packmol using fpm

Source: https://github.com/m3g/packmol/blob/master/README.md

Compiles the Packmol package using the Fortran Package Manager (fpm). This method automates the build process and places the executable in a directory included in the system's PATH, simplifying access.

```bash
# Ensure FPM_FC is set if not using gfortran, e.g., export FPM_FC=ifort
fpm install --profile release
```

--------------------------------

### Pack Water Molecules into a Box using Python

Source: https://context7.com/m3g/packmol/llms.txt

This Python function demonstrates how to use Packmol programmatically via the subprocess module. It creates an input file and runs Packmol to pack water molecules into a specified cubic box. Dependencies include the `subprocess` and `pathlib` modules.

```python
import subprocess
from pathlib import Path

WATER_XYZ = """
3
water molecule
O   0.000   0.000   0.000
H   0.957   0.000   0.000
H  -0.240   0.927   0.000
"""

def pack_water_box(tmp_path: Path, num_molecules: int = 10):
    """Pack water molecules into a cubic box."""
    # Write water molecule template
    (tmp_path / "water.xyz").write_text(WATER_XYZ)

    # Create input file
    (tmp_path / "input.inp").write_text(f"""
tolerance 2.0
filetype xyz
output output.xyz

structure water.xyz
  number {num_molecules}
  inside box 0. 0. 0. 20. 20. 20.
end structure
""")

    # Run packmol
    result = subprocess.run(
        ["packmol"],
        stdin=open(tmp_path / "input.inp"),
        capture_output=True,
        cwd=tmp_path,
    )

    if result.returncode == 0:
        return tmp_path / "output.xyz"
    else:
        raise RuntimeError(f"Packmol failed: {result.stderr.decode()}")

# Usage
# output_file = pack_water_box(Path("/tmp/packmol_run"), num_molecules=100)
```

--------------------------------

### Packmol Input for Water Box with PBC

Source: https://context7.com/m3g/packmol/llms.txt

Configures a water box with periodic boundary conditions (PBC) using Packmol. This is essential for simulations that require translational symmetry.

```packmol
# Water box with PBC
tolerance 2.0
filetype pdb
output output.pdb
pbc 40. 40. 40.
seed 1

structure water.pdb
  number 1150
end structure
```

--------------------------------

### Build Packmol Executable

Source: https://github.com/m3g/packmol/blob/master/CMakeLists.txt

This CMake command defines the 'packmol' executable and lists all the Fortran source files required to build it. This is the core compilation step for the project.

```cmake
add_executable(packmol
       src/exit_codes.f90
       src/cenmass.f90
       src/gencan.f
       src/gencan_ieee_signal_routines.f90
       src/pgencan.f90
       src/initial.f90
       src/title.f90
       src/setsizes.f90
       src/getinp.f90
       src/strlength.f90
       src/output.f90
       src/cli_parser.f90
       src/checkpoint.f90
       src/writesuccess.f90
       src/fparc.f90
       src/gparc.f90
       src/gwalls.f90
       src/comprest.f90
       src/comparegrad.f90
       app/packmol.f90
       src/polartocart.f90
       src/resetcells.f90
       src/tobar.f90
       src/cell_indexing.f90
       src/restmol.f90
       src/swaptype.f90
       src/swaptypemod.f90
       src/ahestetic.f90
       src/heuristics.f90
       src/flashsort.f90
       src/jacobi.f90
       src/random.f90
       src/sizes.f90
       src/pbc.f90
       src/usegencan.f90
       src/compute_data.f90
       src/flashmod.f90
       src/computef.f90
       src/computeg.f90
       src/input.f90
)
```

--------------------------------

### Configure Packmol Project with CMake

Source: https://github.com/m3g/packmol/blob/master/CMakeLists.txt

This snippet initializes the CMake build system for the Packmol project, specifying the minimum required version and the project name. It also sets the primary programming language to Fortran.

```cmake
cmake_minimum_required(VERSION 3.10)
project(packmol Fortran)
```

--------------------------------

### Configure GCC Fortran Compiler Warnings

Source: https://github.com/m3g/packmol/blob/master/CMakeLists.txt

This snippet adds compiler flags for the GNU Fortran compiler. It enables all warnings (-Wall) and treats warnings as errors in Debug builds, promoting code quality.

```cmake
if(CMAKE_Fortran_COMPILER_ID MATCHES GNU)
    add_compile_options(
        -Wall "$<$<CONFIG:Debug>:-Werror>"
    )
endif()
```

--------------------------------

### Packmol Input using XYZ File Format

Source: https://context7.com/m3g/packmol/llms.txt

Specifies the use of the XYZ file format for both input and output in Packmol. This demonstrates flexibility in handling different molecular file formats.

```packmol
# XYZ file format example
tolerance 2.0
filetype xyz
output output.xyz

structure molecule.xyz
  number 100
  inside box -10. -10. -10. 10. 10. 10.
end structure
```

--------------------------------

### Packmol Input for Fixed Molecules

Source: https://context7.com/m3g/packmol/llms.txt

Places fixed molecules (e.g., ions) at specific positions and adds free molecules within a defined box using Packmol. This is useful for setting up systems with immobile components.

```packmol
# Fixed molecules
tolerance 2.0

structure SOD.pdb
  number 1
  fixed 0. 0. -1. 0. 0. 0.
  centerofmass
end structure

structure SOD.pdb
  number 1
  fixed 0. 0. 1. 0. 0. 0.
  centerofmass
end structure

structure CLA.pdb
  number 1
  inside box -1.0 -1.0 -2.0 1.0 1.0 3.0
end structure

output output.pdb
avoid_overlap no
seed 17504
```

--------------------------------

### Basic Packmol Input File Structure

Source: https://context7.com/m3g/packmol/llms.txt

Defines a basic input file for Packmol, specifying tolerance, output file, file type, and a single structure block with spatial constraints for water molecules.

```packmol
# Basic water box configuration
tolerance 2.0
filetype pdb
output output.pdb

structure water.pdb
  number 1000
  inside box -20. -20. -20. 20. 20. 20.
end structure
```

--------------------------------

### Set Default Build Type to Release

Source: https://github.com/m3g/packmol/blob/master/CMakeLists.txt

This CMake code ensures that if no specific build type is set by the user, the default build type will be 'Release'. This optimizes the executable for performance.

```cmake
if(NOT CMAKE_BUILD_TYPE)
    set(CMAKE_BUILD_TYPE Release)
endif(NOT CMAKE_BUILD_TYPE)
```

--------------------------------

### Packmol Input for Protein Solvation

Source: https://context7.com/m3g/packmol/llms.txt

Solvates a fixed protein structure with water and ions (Chloride and Sodium) within a spherical region using Packmol. It demonstrates fixing a molecule and confining others to a sphere.

```packmol
# Protein solvation
tolerance 2.0

structure protein.pdb
  resnumbers 0
  number 1
  fixed 0. 0. 0. 0. 0. 0.
  centerofmass
end structure

structure water.pdb
  resnumbers 2
  number 1000
  inside sphere 0. 0. 0. 50.
end structure

structure CLA.pdb
  resnumbers 2
  number 20
  inside sphere 0. 0. 0. 50.
end structure

structure SOD.pdb
  resnumbers 2
  number 30
  inside sphere 0. 0. 0. 50.
end structure

output output.pdb
avoid_overlap no
seed -1
```

--------------------------------

### Packmol Input for Lipid Bilayer

Source: https://context7.com/m3g/packmol/llms.txt

Generates a lipid bilayer with water layers above and below using Packmol. This configuration uses plane constraints to orient the lipid molecules correctly.

```packmol
# Lipid bilayer
tolerance 2.0
filetype pdb
output output.pdb

structure water.pdb
  number 50
  inside box 0. 0. -10. 40. 40. 0.
end structure

structure water.pdb
  number 50
  inside box 0. 0. 28. 40. 40. 38.
end structure

structure palmitoil.pdb
  number 10
  inside box 0. 0. 0. 40. 40. 14.
  atoms 31 32
    below plane 0. 0. 1. 2.
  end atoms
  atoms 1 2
    above plane 0. 0. 1. 12.
  end atoms
end structure

structure palmitoil.pdb
  number 10
  inside box 0. 0. 14. 40. 40. 28.
  atoms 1 2
    below plane 0. 0. 1. 16.
  end atoms
  atoms 31 32
    above plane 0. 0. 1. 26
  end atoms
end structure
```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.