exercises:2017_uzh_cp2k-tutorial:wfc
Differences
This shows you the differences between two versions of the page.
Both sides previous revisionPrevious revisionNext revision | Previous revision | ||
exercises:2017_uzh_cp2k-tutorial:wfc [2017/06/28 14:54] – vrybkin | exercises:2017_uzh_cp2k-tutorial:wfc [2020/08/21 10:15] (current) – external edit 127.0.0.1 | ||
---|---|---|---|
Line 1: | Line 1: | ||
- | In order to go beyond GGA and hybrid DFT, one option is to use wave function correlation methods. Recently, second-order Møller-Plesset perturbation theory (MP2) and random phase approximation (RPA) have been added to CP2K [[doi> | + | In order to go beyond GGA and hybrid DFT, one option is to use wave function correlation methods. Recently, second-order Møller-Plesset perturbation theory (MP2) and random phase approximation (RPA) have been added to CP2K . The implementations are aimed at condensed phase calculations, |
- | However, significant computational resources are needed for the condensed phase calculations. Therefore, we will perform the gas phase calculations in this tutorial, even though RI-GPW is not very efficient in this case. | + | However, significant computational resources are needed for the condensed phase calculations |
+ | |||
+ | **Some references: | ||
+ | |||
+ | MP2 and RPA energies implementations in CP2K: | ||
+ | |||
+ | MP2 forces: [[doi> | ||
+ | |||
+ | Cubic scaling RPA implementation: | ||
+ | |||
+ | **Since the correlated wave function calculations are expensive, please use 4 cores for execution (with one OMP thread): | ||
+ | < | ||
+ | mpirun -np 4 -x OMP_NUM_THREADS=1 | ||
+ | </ | ||
===== 1. Task: Benzene dimer MP2 binding energy ===== | ===== 1. Task: Benzene dimer MP2 binding energy ===== | ||
- | Employ the provided input file to compute the benzene dimer binding energy. The provided dimer geometry is optimized already. To obtain the energy of the monomer, geometry optimization is necessary | + | Employ the provided input file to compute the benzene dimer binding energy. The provided dimer geometry is optimized already. To obtain the energy of the monomer, geometry optimization is in principle |
+ | |||
+ | During the optimization of benzene, one will calculate gradient which, in turn, requires density matrices. Hence, one can calculate electronic densities. Add the following to the ''& | ||
+ | < | ||
+ | & | ||
+ | &END | ||
+ | </ | ||
+ | and the following lines to the ''& | ||
+ | < | ||
+ | & | ||
+ | & | ||
+ | &END | ||
+ | &END | ||
+ | </ | ||
+ | |||
+ | Importantly, | ||
+ | < | ||
+ | FREE_HFX_BUFFER .FALSE. | ||
+ | </ | ||
+ | |||
+ | Perform two optimizations setting '' | ||
+ | < | ||
+ | integrate_four_center | ||
+ | </ | ||
+ | The last number in the line is the real time of execution. The memory distribution between the RI-MP2 integrals and HFX integrals are tuned by the '' | ||
+ | < | ||
+ | & | ||
+ | MAX_MEMORY | ||
+ | &END | ||
+ | |||
+ | </ | ||
- | Topics: | + | At the optimized |
- | * RI approach | + | Density differences can be computed with '' |
- | * Wavelet solver ('' | + | |
- | * gas phase HFX calculation | + | |
- | * memory issues ('' | + | |
===== 2. Task: Benzene monomer RPA energy: frequency integration ===== | ===== 2. Task: Benzene monomer RPA energy: frequency integration ===== | ||
- | RPA is HFX+RPA correlation. It can be performed with HFX orbitals and eigenvalues, | + | RPA is HFX+RPA correlation. It can be performed with HFX orbitals and eigenvalues, |
Here, we look at the convergence of the RPA energy as a function of the number of integration points ('' | Here, we look at the convergence of the RPA energy as a function of the number of integration points ('' | ||
Line 52: | Line 92: | ||
====== Required files ====== | ====== Required files ====== | ||
+ | Input files and a wave function restart file can be found in the archive: {{ : | ||
input file for an RI-MP2 calculation on a benzene dimer | input file for an RI-MP2 calculation on a benzene dimer | ||
Line 192: | Line 233: | ||
&MOTION | &MOTION | ||
& | & | ||
- | | + | |
- | | + | |
| | ||
& | & | ||
Line 201: | Line 241: | ||
</ | </ | ||
- | During the optimization of benzene, one will calculate gradient which, in turn, requires density matrices. Hence, one can calculate electronic densities. Add the following to the ''& | ||
- | < | ||
- | & | ||
- | &END | ||
- | </ | ||
- | and the following lines to the ''& | ||
- | < | ||
- | |||
- | & | ||
- | &END | ||
- | &END | ||
- | </ | ||
- | Importantly, | ||
- | < | ||
- | FREE_HFX_BUFFER .FALSE. | ||
- | </ | ||
| |
exercises/2017_uzh_cp2k-tutorial/wfc.1498661653.txt.gz · Last modified: 2020/08/21 10:15 (external edit)