Back to the main page of this manual  Input reference of CP2K version 8.1 
CP2K_INPUT /
FORCE_EVAL /
DFT /
TDDFPT /
XC /
WF_CORRELATION /
LOW_SCALING
&LOW_SCALING {Logical} 

Activates cubicscaling RPA, GW and LaplaceSOSMP2 calculations.  
This keyword cannot be repeated and it expects precisely one logical.  
The lone keyword behaves as a switch to
.TRUE. 

Default value:
.FALSE. 
CUTOFF_W {Real} 

Cutoff for screened Coulomb interaction for GW kpoints.  
This keyword cannot be repeated and it expects precisely one real.  
Default value:
5.00000000E001 
DO_KPOINTS {Logical} 

Besides in DFT, this keyword has to be switched on if one wants to do kpoints in. cubic RPA.  
This keyword cannot be repeated and it expects precisely one logical.  
The lone keyword behaves as a switch to
.TRUE. 

Default value:
.FALSE. 
EPS_FILTER {Real} 

Determines a threshold for the DBCSR based multiply.Normally, this EPS_FILTER determines accuracy and timing of lowscaling RPA and GW calculations.  
This keyword cannot be repeated and it expects precisely one real.  
Default value:
1.00000000E009 
EPS_FILTER_FACTOR {Real} 

Multiply EPS_FILTER with this factor to determine filter epsilon for DBCSR based multiply P(it)=(Mocc(it))^T*Mvirt(it) Default should be kept.  
This keyword cannot be repeated and it expects precisely one real.  
Default value:
1.00000000E+001 
EPS_STORAGE_SCALING {Real} 

Scaling factor to scale EPS_FILTER. Storage threshold for compression will be EPS_FILTER*EPS_STORAGE_SCALING.  
This keyword cannot be repeated and it expects precisely one real.  
Default value:
1.00000000E003 

Alias names for this keyword: EPS_STORAGE 
EXP_KPOINTS {Real} 

For kpoints in lowscaling GW, a MonkhorstPack mesh is used. Because the screened Coulomb interaction W(k) diverges at the Gamma point with W(k) ~ k^alpha, we adapt the weights of the MonkhorstPack mesh to compute int_BZ k^alpha dk (BZ=Brllouin zone) correctly with the MonkhorstPack mesh. You can enter here the exponent alpha. For solids, the exponent is 2 (known from plane waves), for 2d periodic systems 1 and for 1d systems W(k) ~ log(1cos(a*k)) where a is the length of the unit cell in periodic direction. If you enter 1.0, one of these three functions are picked according to the periodicity. If you enter a value bigger than 2.0, the ordinary MonkhorstPack mesh with identical weights is chosen.  
This keyword cannot be repeated and it expects precisely one real.  
Default value:
1.00000000E+000 
KPOINTS {Integer} {Integer} {Integer} 

For periodic calculations, using kpoints for the density response and the Coulomb operator are strongly recommended. For 2d periodic systems (e.g. xy periodicity, please specify KPOINTS N_x 0 N_z.  
This keyword cannot be repeated and it expects precisely 3 integers.  
Default values:
0 0 0 
MEMORY_CUT {Integer} 

Reduces memory for sparse tensor contractions by this factor. A high value leads to some loss of performance. This memory reduction factor applies to storage of the tensors 'M occ' / 'M virt' but does not reduce storage of '3c ints'.  
This keyword cannot be repeated and it expects precisely one integer.  
Default value:
5 
MEMORY_INFO {Logical} 

Decide whether to print memory info on the sparse matrices.  
This keyword cannot be repeated and it expects precisely one logical.  
The lone keyword behaves as a switch to
.TRUE. 

Default value:
.FALSE. 
MIN_BLOCK_SIZE {Integer} 

Minimum tensor block size. Adjusting this value may have minor effect on performance but default should be good enough.  
This keyword cannot be repeated and it expects precisely one integer.  
Default value:
5 
MIN_BLOCK_SIZE_MO {Integer} 

Tensor block size for MOs. Only relevant for GW calculations. The memory consumption of GW scales as O(MIN_BLOCK_SIZE_MO). It is recommended to set this parameter to a smaller number if GW runs out of memory. Otherwise the default should not be changed.  
This keyword cannot be repeated and it expects precisely one integer.  
Default value:
64 
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