MolBO

Official Resources

• GitHub: https://github.com/zorkzou/MolBO
• Project Page: https://zorkzou.github.io/MolBO/readme.html
• Related ecosystem: Interfaces MOLPRO outputs with NBO-style workflows

Overview

MolBO is a utility program for generating NBO-47 files from MOLPRO output and for calculating Mayer bond orders. It is a practical bridge between MOLPRO calculations and downstream bonding-analysis workflows that use NBO-compatible data.

Scientific domain: Bond-order analysis, NBO interoperability, MOLPRO post-processing
Target user community: MOLPRO users needing Mayer bond orders or NBO-style downstream analysis

Theoretical Methods

• Mayer bond order calculation
• NBO-47 file generation
• Extraction of overlap, Fock, and density matrices from MOLPRO outputs

Capabilities (CRITICAL)

• Generates NBO-47 files from MOLPRO output
• Calculates Mayer bond orders directly
• Supports a wide range of MOLPRO methods according to the project documentation
• Serves as a practical interface between MOLPRO and NBO-style bonding analysis
• Public source repository and project page available

Sources: Official GitHub repository and project readme

Key Strengths

MOLPRO-Specific Utility:

• Tailored to MOLPRO output structure
• Helpful when direct downstream bonding analysis is cumbersome
• Bridges MOLPRO with NBO-related workflows

Bonding Metrics:

• Mayer bond orders included
• Reads necessary matrix data from MOLPRO output
• Supports many correlated and multireference methods documented by the project

Practical Interoperability:

• Complements Molden2AIM rather than replacing it
• Useful for format preparation and bond-order extraction
• Clear feature/limitation documentation on the project page

Inputs & Outputs

• Input formats:

  • MOLPRO output files with the required printed matrix information

• Output data types:

  • NBO-47 files
  • Mayer bond orders

Workflow and Usage

1. Run a MOLPRO calculation with the required printed matrices.
2. Feed the MOLPRO output into MolBO.
3. Generate the NBO-47 file and/or extract Mayer bond orders.
4. Use the outputs in downstream bonding-analysis workflows.

Performance Characteristics

• Lightweight task-specific utility
• Best suited to MOLPRO-centered post-processing
• Valuable in workflows where direct bond-order extraction or NBO interfacing is needed

Limitations & Known Constraints

• MOLPRO dependence: Only relevant for MOLPRO users
• Input requirements: Requires specific printed matrices in the output
• Symmetry limitations: Repository notes restrictions involving symmetry-equivalent atoms

Comparison with Other Tools

• vs Molden2AIM: MolBO is MOLPRO-specific and includes Mayer bond orders; Molden2AIM is a broader Molden-to-AIM/NBO converter
• vs NBO: MolBO prepares NBO-compatible input rather than replacing the NBO analysis engine
• Unique strength: MOLPRO-specific NBO-47 generation plus Mayer bond orders

Application Areas

• Bond-order analysis for MOLPRO calculations
• Preparing NBO-compatible files
• Interoperability in correlated-wavefunction workflows
• Weak and covalent interaction studies using Mayer bond orders

Community and Support

• Public GitHub repository
• Project readme and example guidance
• Useful niche tool in the Molpro/NBO interoperability space

Verification & Sources

Primary sources:

1. GitHub: https://github.com/zorkzou/MolBO
2. Project page: https://zorkzou.github.io/MolBO/readme.html
3. Repository documentation describing NBO-47 generation and Mayer bond orders

Confidence: VERIFIED

Verification status: ✅ VERIFIED

• Public repository: ACCESSIBLE
• Documentation: AVAILABLE
• Primary use case: MOLPRO-to-NBO interoperability and Mayer bond-order analysis