System displacement can cause force calculation errors

[ESROAMER]

Describe the bug

During my tests on the CO molecule, I found that if the entire molecule undergoes a displacement, the resulting force differs significantly. This seems absurd to me. Molecular structure (before and after displacement)：

Forces in MD_dump(before and after displacement)

Since CO is a linear molecule aligned along the z-axis, no forces should be generated in the xy directions. Clearly, the latter results contain errors.

Expected behavior

No response

To Reproduce

Use my input files to reproduce

MD.zip

ABACUS version: commit f16364d (latest version for now)

Environment

No response

Additional Context

No response

Task list for Issue attackers (only for developers)

• [ ] Verify the issue is not a duplicate.
• [ ] Describe the bug.
• [ ] Steps to reproduce.
• [ ] Expected behavior.
• [ ] Error message.
• [ ] Environment details.
• [ ] Additional context.
• [ ] Assign a priority level (low, medium, high, urgent).
• [ ] Assign the issue to a team member.
• [ ] Label the issue with relevant tags.
• [ ] Identify possible related issues.
• [ ] Create a unit test or automated test to reproduce the bug (if applicable).
• [ ] Fix the bug.
• [ ] Test the fix.
• [ ] Update documentation (if necessary).
• [ ] Close the issue and inform the reporter (if applicable).

[ESROAMER]

I used a vacuum layer significantly larger than the orbital cutoff radius, which should effectively prevent any interactions between atoms in neighboring unit cells.