A sample Aces 2 input file for H

Test run on water <------------------- your comment (ignored by Aces 2) O <------------------- Z matrix H 1 roh* <------------------- Z matrix (* indicates optimization) H 1 roh* 2 ang* <------------------- Z matrix (* indicates optimization) blank line roh=0.957 <------------------- initial value of roh ang=104.5 <------------------- initial value of ang blank line *ACES2(SYMMETRY=ON,BASIS=CC-PVDZ,CALCLEVEL=CCSD[T],UNITS=ANGSTROM <---- job control parameters REFERENCE=RHF,SCF_EXPSTAR=1,DROPMO=1 <---- job control parameters SPHERICAL=ON,MEM=10000000,SCF_CONV=12,SCF_MAXCYC=300,CC_CONV=9) <---- job control parametersThis input file corresponds to geometry optimization (*'s designate the parameters to be optimized), using the CCSD(T) method (CALCLEVEL=CCSD[T]) and the cc-PVDZ basis set (BASIS=CC-PVDZ). The lowest orbital is kept frozen (DROPMO=1) and the calculation utilizes the point symmetry of H

And here is another input, corresponding to
calculations of vertical excitation energies of CH^{+}
with the EOMCCSD approach.

Test run on CH+ <------------------- your comment (ignored by Aces 2) C 0.0000000000 0.0000000000 0.0000000000 <------------------- Cartesian coordinates of the C nucleus H 0.0000000000 0.0000000000 2.1371300000 <------------------- Cartesian coordinates of the H nucleus blank line *ACES2(SYMMETRY=ON,BASIS=AUG-CC-PVDZ,CALC=CCSD,UNITS=BOHR,EXCITE=EOMEE <---- job control parameters ESTATE_SYM=3/0/0/0,COORDINATE=CARTESIAN,CHARGE=1 <---- job control parameters SPHERICAL=OFF,MEM=100000000,SCF_CONV=12,SCF_MAXCYC=300,CC_CONV=12) <---- job control parametersAs you can see, you can use Carterian coordinates instead of Z-matrix and bohr instead of Angstrom. ESTATE_SYM=3/0/0/0 means that you are interested in three excited states of the

The final example corresponds to a calculation of vibrational harmonic frequencies of the ammonia molecule.

Test run on ammonia <------------------- your comment (ignored by Aces 2) N <------------------- Z matrix H 1 hn2 <------------------- Z matrix H 1 hn3 2 hnh3 <------------------- Z matrix H 1 hn4 3 hnh3 2 dih4 <------------------- Z matrix blank line hn2=1.0272884788 <------------------- value of hn2 hn3=1.0272258373 <------------------- value of hn3 hn4=1.0272884788 <------------------- value of hn4 hnh3=103.5344646668 <------------------- value of hnh3 dih4=-107.7934123471 <------------------- value of dih4 blank line *ACES2(SYMMETRY=ON,BASIS=CC-PVDZ,CALCLEVEL=CCSD[T],UNITS=ANGSTROM <---- job control parameters REFERENCE=RHF,SCF_EXPSTAR=1,DROPMO=1,VIB=FINDIF <---- job control parameters SPHERICAL=ON,MEM=200000000,SCF_CONV=12,SCF_MAXCYC=300,CC_CONV=9) <---- job control parametersThe calculation uses the CCSD(T) method (CALCLEVEL=CCSD[T]) and the cc-pvdz basis set (BASIS=CC-PVDZ). VIB=FINDIF means that the force constant matrix is computed by finite difference of analytically computed gradients or energies using symmetry-adapted mass-weighted Cartesian coordinates. In this example, the second derivatives defining the force constant matrix are calculated by numerically differentiating the analytically computed gradients (first derivatives), which saves you a lot of computer time, since at least first derivatives are calculated analytically. The fact that you can do such things at the very high CCSD(T) level is a fairly unique feature of Aces 2. Notice the absence of *'s at variables used in Z matrix (geometry is not optimized in this example).

Note: in the above line, your input file is assumed to be named

The output file will be called

You will also see the extra file OLDMOS_aces_file, which contains molecular orbitals for various restart calculations (you can erase this file, if you do not need it).

To learn more about the NQS queue system running in the department, go here.