Question: Rationale behind using contributeHk instead of contributeHR for EXX in RT-TDDFT

[xuan112358]

Details

While looking into the implementation of Exact Exchange (EXX) within the RT-TDDFT module, I noticed that the EXX contribution is added via contributeHk rather than contributeHR.
In most other modules (such as ground-state SCF), the Hamiltonian contributions are typically handled through contributeHR.
What is the specific consideration for using contributeHk in the EXX RT-TDDFT implementation?
I am concerned that bypassing contributeHR might lead to some "hidden" issues. For instance, I noticed a previous pr #7344 fixed a bug related to EXX contributions that was exactly caused by this kind of discrepancy.

Have you read FAQ on the online manual http://abacus.deepmodeling.com/en/latest/community/faq.html

• Yes, I have read the FAQ part on online manual.

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