ACES II User manual version 2.7.0 (PDF) - Quantum Theory Project

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2 PrefaceThis manual is maintained as a set of L A TEX documents under CVS control along with theACES II source code. Every version of the code has an accompanying manual, and whilethe user interface is relatively stable, it is not guaranteed that the manual of one version iscompatible with binary executables of a different version. Any errors in the manual shouldbe reported to aces2@qtp.ufl.eduThe goal of this manual is to provide beginners and experts alike with enough informationto run any calculation that the software allows. A reference section is provided for furtherreading on the theories and algorithms implemented in the program.9
3 IntroductionACES II is a set of programs that performs ab initio quantum chemistry calculations.The package has a high degree of flexibility and supports many kinds of calculations at anumber of levels of theory. The major strength of the program system is using “many-body”methods to treat electron correlation. These approaches, broadly categorized as many-bodyperturbation theory (MBPT) and the coupled-cluster (CC) approximation, offer a reliabletreatment of correlation and have the attractive property of size-extensivity, which meansthe energies scale properly with the size of the system. As a result of this property, MBPTand CC methods are ideally suited for the study of chemical reactions. While ACES II canperform Hartree-Fock Self-Consistent-Field (HF-SCF) and Kohn-Sham Density FunctionalTheory (KS-DFT) calculations, the ACES II program system is not intended for large scaleHF-SCF or KS-DFT calculations.Two important features of the ACES II program system are its effective use of molecularsymmetry, particularly in MBPT and CC calculations, and the sophisticated gradientmethods which are included in the program. Even if a few elements of symmetry are presentin a molecular system, differences in execution times required for calculations with symmetryand without can be dramatic. The implementation of symmetry currently is limited toD 2h and its subgroups, and the expected speedup due to symmetry utilization will be onthe order of the square of the order of the computational point group for all steps exceptintegral and integral derivative generation and integral sorts, in which the speedup can beno greater than the order of the group.Gradient techniques are implemented for SCF and the following correlated levels of theory:MBPT(2), MBPT(3), MBPT(4), CCD, QCISD, CCSD, QCISD(T), and CCSD(T) forboth restricted and unrestricted Hartree-Fock (RHF and UHF, respectively) reference functions.In addition, for the MBPT(2), MBPT(3), CCSD, and CCSD(T) methods, gradientsare available for restricted open-shell Hartree-Fock (ROHF) reference functions. They arealso available for certain CCSD calculations based on quasi-restricted Hartree-Fock (QRHF)reference functions, namely those for high-spin doublet cases and two-determinant CCSD(TD-CCSD) calculations for open-shell singlet states, in which the open-shell orbitals havedifferent symmetries.Efficient algorithms for geometry optimization and transition state searching have alsobeen included, and may be used at all levels of theory. The analytical gradients employedduring geometry optimizations and vibrational frequency calculations depend on their availability.When analytical gradients are not available, automated finite differencing procedurescan be used to compute the derivatives. Analytic second derivatives have been implementedfor SCF using RHF, UHF, and ROHF reference functions. In addition, analyticallyevaluated NMR chemical shift tensors are available at the SCF and MBPT(2) levels using10
Page 1 and 2: ACES II Release 2.5.0User ManualDRA
Page 3 and 4: 5.24 cphf . . . . . . . . . . . . .
Page 5 and 6: 8.1.19 Excited states: ionizations
Page 7 and 8: A.3.4 *EA EOM, *EA CI, *DEA EOM, *D
Page 9: • Equation-of-motion CCSD calcula
Page 13 and 14: Single point energy calculations:
Page 15 and 16: 4 Quickstart GuideAt the bare minim
Page 17 and 18: 5.5 vmol2jaxvmol2ja creates most of
Page 19 and 20: 5.20 propsxprops computes all of th
Page 21 and 22: For example, a user might be nursin
Page 23 and 24: 6 File Structure6.1 ZMATZMAT is the
Page 25 and 26: 6.10.4 OPTARC/OPTARCBKThe iteration
Page 27 and 28: 7 File Formats7.1 ZMAT7.1.1 File an
Page 29 and 30: Line 1 RHF MBPT(2) property calc of
Page 31 and 32: For groups with ambiguities (D 2 ,
Page 33 and 34: the Z matrix. Positions 3 ∗ I −
Page 35 and 36: For example, in a regular hexagonal
Page 37 and 38: and 31 from the correlated calculat
Page 39 and 40: Line Fortran format Description1 A8
Page 41 and 42: hash symbol (#) in the next line to
Page 43 and 44: 8 Keywords8.1 *ACES2 namelistThe us
Page 45 and 46: Controls the creation, updating, an
Page 47 and 48: This keyword can be used to reduce
Page 49 and 50: DIRECT = (switch) OFFControls wheth
Page 51 and 52: =MOREAD → JOBARC file=CORE → co
Page 53 and 54: SCF EXPORDER (previously RPP ORDER)
Page 55 and 56: [NOTE: Gradients and property calcu
Page 57 and 58: SAVE INTS = (switch) OFFControls de
Page 59 and 60: Sets how often the largest T amplit
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8.1.17 Excited states: affinitiesEA
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ESTATE SYM=3-1-0-2 specifies that 6
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8.1.21 PropertiesPROPS = (handle) O
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8.1.22 Geometry optimization: gener
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8.1.25 Geometry optimization: integ
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9 Examples9.1 Single-point calculat
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9.1.5 Effective core potentialsCRF6
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OLDAOMOS and transformed to the cur
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framework. Any other result means t
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• IOPU controls U matrix printing
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adding an electron.The keywords suc
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calculation of chemical shifts can
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198.890 (tzp/dz), and 197.191 (tzp/
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H 5 RHX* 2 A 1 TM6H 6 RHX* 2 A 1 T1
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This example reinforces the default
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X 1 RN 2 R 1 TDAN 2 R 1 TDA 3 TN 2
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10 Parallelization10.1 OverviewACES
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10.2.2 Shared scratch directoriesIf
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10.3 Examples10.3.1 Parallel finite
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alias xj=’xjoda -rank $rank -proc
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11 Troubleshooting11.1 Common mista
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12 ReferencesOf the many methods cu
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• J.D. Watts and R.J. Bartlett, J
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12.4 Analytical second derivatives
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• M.S.Gordon, J.S.Binkley, J.A.Po
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Polarization exponents from correla
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A.2 Kohn-Sham DFT namelistsA.2.1*VS
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A.3 mrcc namelistsA.3.1A.3.2A.3.3A.
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exponents are: H, He (0.75); Li (0.
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svp,dzp,tzp,tzplarge,qz2p,... These
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Table 1: The number of contracted A
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CQueue ScriptsWhile nothing prevent
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Index*ACES2ABCDFULL, 56ABCDTYPE, 55
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TAMP SUM, 57TDHF, 64TRANS INV, 68TR
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ACES II User manual version 2.7.0 (PDF) - Quantum Theory Project

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