Questions tagged [reduced-density-matrix]
For questions about (or involving) reduced density matrices.
8 questions
5 votes
0 answers
153 views
What are the equations to calculate the 2RDMs from coupled cluster amplitudes?
A converged CCSD gradient calculation will show the lagrange multipliers (l1 and l2) and excitation amplitudes (t1 and t2). While many codes do not directly give access to the 2RDM, the tensor l2, t2 ...
- 1,276
4 votes
1 answer
452 views
Is the one-electron reduced density matrix enough in DFT?
There is a conceptual mismatch in my personal understanding between the role of reduced density matrices in DFT and post-HF methods (possibly due to different discussions in textbooks), and I can not ...
- 634
4 votes
0 answers
199 views
What is a relaxed reduced density matrix?
I am trying to understand how to calculate electronic properties using reduced density matrices from electronic structure calculation. So far, I understand (I think) that for the expectation value of ...
- 634
4 votes
1 answer
682 views
What's the best code for getting 1-particle and 2-particle density matrices with CCSD(T) in Python?
I have been using PySCF to calculate the 1-particle and 2-particle density matrix from ccsd(T) wavefunction using these modules in-built in PySCF make_rdm1() and <...
- 1,276
5 votes
2 answers
483 views
Interface between PySCF and Molpro
I am currently interested in using pySCF to generate density matrices (first order single particle density matrices) and then using them in Molpro. In principle, this should be possible if the matrix ...
- 625
7 votes
1 answer
2k views
What information does the 1RDM contain?
The one-electron reduced density matrix (1RDM) contains information useful for the prediction of molecular properties (for instance, dipole moments). As an example, the 1RDM can be easily obtained in ...
- 2,231
10 votes
1 answer
3k views
Convert reduced density matrix from M.O. to A.O. basis
I am interested in converting the one-particle reduced matrix (rdm1) from the molecular orbital (M.O.) basis to the atomic orbital (A.O.) basis. Is the following method correct (in an identical ...
- 2,231
17 votes
1 answer
455 views
How are one-/two- particle reduced density matrices printed in mainstream programs?
The FCIDUMP format is widely used for the communication of one- and two- body integrals. I wonder what formats are used for 1-/2-RDMs, which are important in many basis rotation or compression tasks. ...
- 1,096