! EXAM32.
! Test of Coupled-Cluster energy for HNO
! The basis set used is 6-31G(d,p), with 35 AOs.
! An advanced non-iterative triples energy is
! computed, which should be better than CCSD(T).
! The two chemical core orbitals are not correlated.
!
! RHF FINAL E= -129.7891059395 after 13 iters
! Highest level result is E(CR-CC(2,3))= -130.1517479953
!
! Other results are
! 19 CCSD iterations needed to converge T1 and T2.
! E(MBPT(2)) = -130.1278985212, aka MP2 energy
! E(CCSD) = -130.1398314377
! The T1 diagnostic is 0.01448788, and the largest T2
! amplitude is for the pi->pi* double, namely -0.146352.
! It takes 15 iterations to converge the left eigen-
! state (lambda equation). A number of other
! "completely renormalized" energies are computed, with
! CR-CCL aka CR-CC(2,3),D being considered the best.
! The CCSD level dipole is 1.658371 Debye
!
! The "standard" E(CCSD(T)) is not computed by this run,
! change to CCTYP=CCSD(T) to see that.
!
$contrl scftyp=rhf cctyp=cr-ccl runtyp=energy nzvar=3 $end
$system timlim=2 $end
$guess guess=huckel $end
$basis gbasis=n31 ngauss=6 ndfunc=1 npfunc=1 $end
$zmat izmat(1)=1,1,2, 1,2,3, 2,1,2,3 $end
$data
HNO...CR-CC(2,3) computation in small DZP basis
Cs
H 1.0 -0.3153213523 0.9784305023 0.0
N 7.0 0.0188021294 0.0012704060 0.0
O 8.0 1.1940439356 0.0007180427 0.0
$end

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Link to the log file of this example.

exam32 Log File

created on 6/20/2013