how to define maxact

Dear Kallay,

I am doing a very large calculation. I wan to use maxact to limit cluster of excitation so that the computation could be smaller. I try maxact, but it go error. Do I maxact incorrectly. The manual does not provide more information to figure out how to define maxact for me. Thank you for you help!

iface=dirac
calc=CCSDT
mem=150000MB
symm=0
dens=5
nstate=2
maxact=on
0 0 3
ciguess=on
1
1 1 11 10 1.0
refdet=vector
1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0



Memory requirements /Mbyte/:
Minimal Optimal
Real*8: 42.5404 7321.4506
Integer: 88.6885
Total: 131.2289 7410.1391

************************ 2015-10-23 15:48:58 *************************
Executing mrcc...
**********************************************************************
LR-CCSDT transition moment calculation


OpenMP parallel version is running.
Number of CPUs: 10
Allocation of 7321.5 Mbytes of memory...
Number of spinors: 176
Number of electrons: 19
Number of active particles: 0
Number of active holes: 19
z-component of spin: 9.5
Spatial symmetry is not used.
Convergence criterion: 1.0E-08
Construction of occupation graphs...
Number of 0-fold excitations: 0
Number of 1-fold excitations: 0
Number of 2-fold excitations: 0
Number of 3-fold excitations: 0
Total number of determinants: 0
Calculation of coupling coefficients...
Initial cluster amplitudes are generated.
Length of intermediate file (Mbytes): 0.0
Reading integral list from files MRCONEE and MDCINT...
Sorting integrals...
Energy of reference determinant [au]: -5572.523897431885
Reading property integrals from file MDPROP...
Length of property integral file (Mbytes): 0.0
Property value for ref. det., X-DIP: -0.000000000219
Sorting integrals...
Property value for ref. det., EOFLABEL: 0.000000000000
Sorting integrals...
Property value for ref. det., EOFLABEL: 0.000000000000
Sorting integrals...
Calculation of diagonal elements of Hamiltonian...
Invalid number of roots!

Fatal error in mrcc.
Program will stop.

Dear Yanmei,
You should first define the active/inactive orbitals using the active keyword. The maxact keyword can only be used if these are defined. Please note maxact sets the maximum number inactive labels, so probably you need:

maxact=on
1 2 0

Dear Kallay,

Thank you very much. We set active, then MRCC run normally.

By guess, we define the highest occupation orbital and the lowest virtual orbital to be active. This is just transition what we ask for. We are still thinking the meaning of the active set. If you can give more explantion about the computational ideas behide "active" defination, it would be very helpful to us. Does it mean to prepare a multi-reference for the CC calculation?

active=vector
0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Dear Yanmei,
In the way you use the CCSDT + maxact + active keyword combination is practically a reduced-cost single-reference CCSDT where the triple excitations can only excite within the active space. This approach is also known as CCSDt. However, to get a reliable estimate for the CCSDT energy, you should use bigger active spaces, e.g., all the occupied orbitals + at least one third of virtuals.

Dear Kallay,
It's much clearer, now I see, thank you very much.

yanmei

Dear Kallay,

I am afraid I still do not get it correctly. As you suggestion, I set active all occupied and some virtural orbitals. I have 190 orbitals in total. The first 95 are alpha and the following 95 are beta orbitals. If I set all occupied and some virtural alpha orbitals active, the calculation run normally, but when I try to set the occupied beta orbitals also active, the calcualtion stop by error. I cannot understand what's the problem. Thank you for your help again.

Input file: this input works normal

iface=dirac
calc=CCSDT
mem=150000MB
symm=0
dens=5
nstate=2
active=vector
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
maxact=on
1 2 2
maxex=3
ciguess=on
1
1 1 11 10 1.0
refdet=vector
1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

But the following Input file leads to stop errors, why?

iface=dirac
calc=CCSDT
mem=150000MB
symm=0
dens=5
nstate=2
active=vector
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
maxact=on
1 2 2
maxex=3
ciguess=on
1
1 1 11 10 1.0
refdet=vector
1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0