[DFTB-Plus-User] Binding energy

[Christopher Mark Maupin]

All,

I have been attempting to reproduce some binding energy calculations for 
water clusters (J.Phys.Chem.A. 111,2007, 10861).
I have attached my results and the previously published results in 
addition to my dftb_pin.hsd file.  The problem is that I am unable to 
reproduce their binding energies.  Has anyone else attempted these 
calculations?
Any help would be greatly appreciated

Best wishes,

Mark



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system  | energytotal (H)  |  binding energy   |  J. Phys. Chem. A. 111, 
2007, 10861 |  highlevel           |
------------------------------------------------------------------------------------------------------------------------------------
H2O    |  -4.0779379194  |          n/a              |                   
n/a                                     |     n/a                  |
2H2O  |  -8.1604464474  |  -2.87 kcal/mol    |                -3.3 
kcal/mol                        |  -4.9 kcal/mol     |
3H2O  | -12.2472510084 |  -8.43 kcal/mol    |                -9.6 
kcal/mol                        | -15.1 kcal/mol    |

the hight level column is also from the cited manuscript.

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Geometry = GenFormat {
3  C
O H
1    1    0.0 0.0 0.0
1    2    1.0 0.0 0.0
1    2    1.2 -1.0 0.0
}
Driver = ConjugateGradient {
  MaxForceComponent = 1e-4
  MovedAtoms = Range {
 1 -1
  }
  MaxSteps = 200
  OutputPrefix = "geo_end"
  AppendGeometries = No
  Constraints = {}
}
Hamiltonian = DFTB {
  SCC = Yes
  SCCTolerance = 1.00E-6
  MaxAngularMomentum = {
    O = "p"
    H = "s"
  }
  SlaterKosterFiles = Type2FileNames {
    Separator = "-"
    Suffix = ".skf"
    Prefix = ""
    LowerCaseTypeName = No
  }
  OrbitalResolvedSCC = No
  OldSKInterpolation = No
  MaxSCCIterations = 100
  Mixer = Broyden {
    MixingParameter = 0.200000000000000
    CachedIterations = -1
    InverseJacobiWeight = 1.000000000000000E-002
    MinimalWeight = 1.00000000000000
    MaximalWeight = 100000.000000000
    WeightFactor = 1.000000000000000E-002
  }
  ElectricField = {}
  DampXH = No
  Charge = 0.000000000000000E+000
  ReadInitialCharges = No
  SpinPolarisation = {}
  Eigensolver = DivideAndConquer {}
  Filling = Fermi {
    Temperature = 1.000000000000000E-008
  }
  OrbitalPotential = {}
  Dispersion = {}
  LocalPotentials = {}
}
Options = {
  WriteAutotestTag = Yes
  WriteEigenvectors = No
  WriteDetailedXML = No
  WriteResultsTag = No
  WriteDetailedOut = Yes
  WriteBandOut = Yes
  AtomResolvedEnergies = No
  RandomSeed = 0
  MinimiseMemoryUsage = No
}
ParserOptions = {
  ParserVersion = 3
  WriteHSDInput = Yes
  WriteXMLInput = No
  StopAfterParsing = No
  IgnoreUnprocessedNodes = No
}
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