Printing of MOs.
|0||Default: 1 for molecules, 2 for PBC.|
|1||Print the occupied and first 5 virtual MOs.|
|2||Do not print any MOs.|
|3||Print all MOs.|
|10||Biorthogonalize unrestricted MOs.|
|100||Save biorthogonalized MOs over canonical ones.|
Density matrix. Default: No-print. See below for values.
Full population analysis. Default: Print. See below for values.
Gross orbital charges. Default: Print. See below for values.
Gross orbital type charges. Default: No-print. See below for values.
Condensed to atoms. Default: Print. See below for values.
These options are print/no-print options. The possible values are:
|1||Print the normal amount.|
|2||Do not print.|
Whether to save computed electric field on disk for use in Tomasi RF calculations.
|1||Evaluate the electric potential, the electric field, and the electric field gradient at each center.|
|2||Evaluate the potential and the electric field at each center.|
|3||Evaluate only the potential at each center.|
Specification of additional centers. If more than one of these is requested, the lists are in separate input sections in the order listed below.
|0||No additional centers. Evaluate the properties only at each atomic center.|
|1||Read additional centers. One card per center with the X, Y, and Z coordinates in Angstroms (free format).|
|2||Read in coordinates as for 1. Starting at each point, located the nearest stationary point in the electric potential.|
|4||Read in a set of cards specifying a grid of points at which the electric potential will be computed. Two forms of specifications are below.|
|8||Do potential-derived charges.|
|16||Constrain the dipole in fitting charges.|
|32||Read in centers at which to evaluate the potential from the RWF.|
|128||Read grid; do not default cube.|
Grid specifications for option 4
A. Evenly spaced rectangular grid. Three cards are required:
|KTape,XO,YO,ZO||—output unit and coordinates of one corner of grid. If KTape is 0, it defaults to 51.|
|N1,X1,Y1,Z1||—number of increments and vector.|
|N2,X2,Y2,Z2||—number of increments and vector.|
N1 records will be written to unit KTape, with N2 values in each record.
B. An arbitrary list of points. Only one card is needed: N,NEFG,LTape,KTape.
The coordinates of N points in Angstroms will be read unit LTape in format (3F20.12). The potential (NEFG=3), potential and field (NEFG=2), or potential, field, and field gradient (NEFG=1) will be computed and written along with the coordinates to unit KTape in format (4F20.12). Thus if NEFG=3 for each point there will be 4 cards written per point, containing:
Note that either form of grid should be specified with respect to the standard orientation of the molecule.
|0||Use full accuracy in calculations at specific points, but use sleazy cutoffs in mapping a grid of points.|
|1||Do all points to full accuracy.|
|0||Compute all contributions to selected properties.|
|1||Compute only the nuclear contribution.|
|2||Compute only the electronic contribution.|
|-N||Compute only the contribution of shell N.|
Whether to update dipole RWF.
Whether to rotate exact polarizability before comparing with approximate (which will be calculated in the standard orientation). This is like IOp(6/9) in L9999.
|0||Default, same as 1.|
|1||Exact is still in standard orientation; use as-is.|
|2||Exact is already in z-matrix orientation, so rotate.|
How to do electrostatic-potential derived charges.
|-1||Read a list of points at which to fit, one per line.|
|1||Merz-Kollman point selection.|
|2||CHELP point selection.|
|3||CHELPG point selection.|
|4||MK but with 2xUFF radii.|
|5||Hu, Lu, and Yang point selection/weighting. By default, HLY’s atomic densities are used. These are available only up to Ar.|
|00||Default radii are those defined with the selected method.|
|10||Force Merz-Kollman radii.|
|15||Use Gaussian’s atomic density expansions instead of HLY’s. Gaussian’s are defined for all elements up to 112.|
|20||Force CHELP (Francl) recommended radii.|
|30||Force CHELPG (Breneman) recommended radii.|
|40||Force 2xUFF Radii.|
|100||Read in replacement radii for selected atom types as pairs (IAn,Rad) or (Symbol,Rad), terminated by a blank line.|
|200||Read in replacement radii for selected atoms as pairs (I,Rad), terminated by a blank line.|
|1000||Fit united atoms (heavy atoms only) rather than all atoms.|
|10000||Use only active atoms in the fit.|
|20000||Use all atoms in the fit.|
|30000||Fix the charges of all atoms with a non-zero MM charge.|
|-1x||Read density matrices from .checkpoint file.|
|+1x||Read density matrices from .checkpoint file.|
|-5||All available transition densities.|
|-4||Transition density between the states given by IOp(6/29) and IOp(6/30).|
|-3||Density for the excited state given by IOp(6/29).|
|-2||Use all available density matrices.|
|-1||Use the density matrix for the current method, or the HF density if the one for the current method is not available.|
|N≥0||Use the density matrix for method N (see Link 1 for the numbering scheme).|
|0||Default (same as 3).|
|2||Density values and gradients.|
|3||Density values, gradients and divergence.|
|-N||Freeze N orbitals.|
|1||Yes, classically (including self terms — requires 2e integrals, O(N4)).|
|2||Yes, quantum mechanically (no self terms — requires 2e integrals, and only available for HF. O(N5)).|
|0||Default (same as 1).|
Choice of population analysis.
|1||Don’t do Mulliken populations.|
|2||Do Mulliken populations.|
|10||Don’t do bonding Mulliken populations.|
|20||Do bonding Mulliken populations.|
|100||Do minimal population analysis.|
|1000||Read in weightings for atoms pairs for unequally split Mulliken.|
Mark SCF density as current density.
|0||No: save SCF density, but do not mark.|
|1||Yes: mark as well.|
Excited state to use if requested by IOp(6/22).
2nd excited state for transition density.
|0||Transition density between state IOp(6/29) and g.s.|
|N||Transition density between state IOp(6/29) and state N.|
Whether to determine natural orbitals from densities.
|1||Yes, using total density.|
|2||Yes, using alpha and beta separately for UHF.|
|3||Store only alpha NOs.|
|4||Store only beta NOs.|
|5||Use spin density.|
|IPrSma||When printing MOs in terms of AOIMs, include only MOs with occupancies per spin greater than 10-IPrSma and AOIMs with squares of coefficients greater than 10-IPrSma (1…9, the default of 0 implies printing of all MOs and AOIMs).|
|MItLoc||MItLoc*NOrb*(NOrb-1)/2 is the maximum number of iterations in localization of (spin) orbitals (1…9, default 6).|
|ITlLoc||10.-ITlLoc is the convergence criterion for (spin)orbital localization (1…9, default 9).|
|IDcInt||Localized (spin)orbitals with atomic occupancies less than 0.01*IDcInt are interpreted as lone pair MOs rather than bond MOs (1…99, default 10).|
|IPrLoc||0: Print the atomic occupancies of localized (spin)orbitals (default).
1: Do not print the atomic occupancies.
|0||Make this a scratch file.|
|1||Name this file ‘rpac.11’|
|0||Determine attractors, attractor interaction lines, ring points, and cage points.|
|1||Determine zero-flux surfaces (IDoZrF).|
|2||Compute charges of AIMs (IDoAtC).|
|4||Compute kinetic energies and multipole moments of AIMs (IDoPrp).|
|10||Compute energies of electrostatic interactions between AIMs (IDoPot). This precludes calculations of atomic property derivatives with respect to nuclear displacements.|
|100||Compute atomic overlap matrices (IDoAOM).|
|200||Compute other atomic matrix elements (IDoAMa).|
|400||Include zero-flux surface relaxation terms in all atomic matrix elements (IDoSRe).|
|1000||Compute derivatives of atomic properties with respect to electric field (IDoSeP). Note that IDoSRe should be set to 1 in order to obtain correct results! Also note that analytical polarizabilities have to be available but force constants have to be absent!|
|2000||Compute derivatives of atomic properties with respect to nuclear displacements as well (IDoNuD). Note that analytical force constants have to be available!|
|10000||Compute localized orbitals and bond orders (IDoLoc).|
|20000||Compute atomic orbitals in molecule (IDoAOs).|
|100000||If necessary, augment valence electron densities with relativistic core contributions, which is a default anyway (IHwAug = 0).|
|200000||If necessary, augment valence electron densities with non-relativistic core contributions (IHwAug = 1).|
|400000||Abort if pseudo-potentials have been used (IHwAug = 3).|
|1000000||Reduce accuracy so atomic charges can be computed more rapidly (IQuick). No other properties can be calculated. This option sets IPrNDe=5, IPrNA t= 5, and IEpsIn = 100.|
|2000000||Use numerical instead of analytic integration.|
|3000000||Use numerical instead of analytic integration and use reduced cutoffs.|
|4000000||Full accuracy and analytic integration.|
|INoZer||0: Ignore (spin)orbitals with zero occupancies (default).
1: Do not ignore (spin)orbitals with zero occupancies.
|IPrNDe||Neglect primitive contributions below 10.-IPrNDe in evaluations of electron density and its derivatives (0…99, default 7).|
|IPrNAt||Neglect primitive contributions below 10.-IPrNAt in integrations over atomic basins (0…99, default 7).|
|MxBpIt||Maximum number of iterations in trial path determination (1…99, default 10).|
|SBpMax||Maximum value of the control sum (1…9, default 2).|
|NGrd||Length of Fourier expansion for the trial path (1…99, default 20).|
|LookUp||Number of grid points in critical point search (1…999, default 100).|
|INStRK||10*INStRK is the number of steps in the Runge-Kutta integrations along gradient paths (1…9, default 2).|
|IHowFa||IHowFa is the maximum distance in the Runge-Kutta integrations along gradient paths (1…9, default 5),|
|IGueDi||10.-IGueDi is the initial displacement from the critical point in the Runge-Kutta integrations (1v9, default 6).|
|IPraIn||10.*IPraIn is the cut-off for zero-flux surfaces (1…9, default 2).|
|IRScal||IRScal is the scaling factor in the nonlinear transformation used in the intersection search (1…9, default 2).|
|IRtFSe||10.*IRtFSe is the safety factor used in the intersection search (1…9, default 2).|
|IToler||10.-5-IToler is the tolerance for the intersection search (1…9, default 5).|
|INInGr||10*INInGr is the initial number of grid points in theta and phi in the adaptive integration subroutine (1…9, default 2).|
|INInCh||5+INInCh is the initial number of sampling points in the intersection search (1…9, default 2).|
|IEpsSf||IEpsSf is the safety factor used for patches with surface faults in the adaptive integration subroutine (1…9, default 6).|
|IEpsIn||0.0001*IEpsIn is the target for integration error (1…99, default 2).|
|INTrig||10*INTrig is the number of sine and cosine functions in the trial function for surface sheets (1…9, default 2).|
|-2||Skip NBO analysis.|
|-1||Do only NPA.|
|1||Default NBO analysis — don’t read input.|
|2||Read input data to control NBO analysis.|
|3||Delete selected elements of NBO Fock matrix and form a new density, whose energy can then be computed by one of the SCF links. This link must have been invoked with IOp(40) = 0 or 1 prior to invoking it with IOp(40) = 2.|
|4||Read the deletion energy produced by a previous run with IOp(40) = 2 and print it.|
|10||NBO should not delete its internal data file.|
Number of layers in esp charge fit.
|N||N layers, must be ≥ 4.|
Density of points per unit area in esp fit.
|N||Points per unit area.|
Increment between layers in MK charge fit.
|0||Default (0.4/Sqrt(#layers)), where # layers = IOP (6/41)|
|0||Default, same as 2.|
|1||Compute the molar volume.|
|2||Evaluate the density over a cube of points.|
|3||Evaluate MOs over a cube of points.|
|10||Skip header information in cube file.|
Number of points per Bohr3 for Monte-Carlo calculation of molar volume.
|-1||Read from input.|
|N||N points — for tight accuracy, 50 is recommended.|
Threshold for molecular volume integration.
|0||Default — 10-3|
|-1||Read from input.|
Scale factor to apply to van der Waals radii for the box size during volume integration.
|N||N*0.01 — for debugging.|
Use of cutoffs.
|0||Default (10-6 accuracy for cubes, 1 digit better than desired accuracy for volumes).|
|-1||Read from cards.|
|-2||Coarse grid, 3 points/Bohr.|
|-3||Medium grid, 6 points/Bohr.|
|-4||Fine grid, 12 points/Bohr.|
|-N>4||Grid using 1000 / N points/Bohr.|
Whether to write Antechamber file during ESP charge fitting.
Whether to apply Extended Koopman’s Theorem (EKT).
|N||Yes, on non-SCF densities, up to N IPs and EAs.|
|-1||Yes, on non-SCF densities, all possible IPs and EAs.|
|N||Polynomial of order N.|
Maximum number of domains.
|-1||0(no inner sphere).|
|N||N point Lebedev grid (see AngQad).|
Whether to generate data over a grid using the total SCF density.
|1||Yes, read in name for output file.|
|2||Yes, also read in name for input file with a different grid and compare.|
|3||Output in the form of data statements.|
|4||Fit atomic density to Gaussians.|
|5||Fit atomic density to Gaussians, forcing positive definiteness.|
Grid to use in generating tables of density and potential if IOp(57) = 1–3. Must be an unpruned grid.
If IOp(57) = 4–5, whether to remove primitives which have all zero coefficients in the expansion:
Approximations to Exc
|-1||Test superposition of atomic densities using L608:|
|0||Do correct energies.|
|1||Do correct energies and 0th order approximation.|
|2||Do correct energies and 0th-1st order approximations.|
|3||Do correct energies and 0th-2nd order approximations.|
Over-ride standard values of IRadAn, IRanWt, and IRanGd. The default is 3 steps smaller grid for HLY charges in L602 and the global default otherwise.
|0||Default (do test).|
|2||Do test as usual.|
Natural Chemical Shielding Analysis.
|1||Yes, of isotropic value.|
|2||Yes, of diagonal tensor elements and isotropic value.|
|3||Yes, of all tensor components.|
Threshold for printing of NCS contributions.
|0||Default (1 pmm).|
|1||Yes, if open-shell, NMR data is available, and other terms are being computed.|
|3||Yes, regardless of other terms.|
|4||Yes, reading isotopes.|
Whether to save orbitals from NBO.
|1||Save NBOs in place of regular MOs.|
|2||Save NLMOs in place of regular MOs.|
|3||Save NLMO occupieds and NBO virtuals.|
Whether to use Gaussian connectivity in choosing Lewis structure for NBO.
|0||Default (use if present and choose is selected in NBO input).|
|N||N * 10-5.|
Use MOs instead of density in AtmTab.
Whether to calculate Hirshfeld charges.
|3||Yes, do atom-atom electrostatic interactions as well.|
|10||Do iterative charges.|
|20||Do iterative charges and read initial values.|
|100||Do partitioning of density by abelian irrep.|
|NNNxxx||Maximum number of iterations. Default is 50.|
Whether to calculate Lowdin charges and Mayer bond orders.
Print kinetic energy of orbitals?
|0||Default (yes, if doing other orbital results).|
|1||Yes, for the top 5 occupieds and lowest 5 virtuals.|
|3||Yes, for all orbitals.|
Tensors for hyperfine spectra.
|0||Default, compute if there are 100 or fewer atoms.|
|1||Compute QEq tensors and for open-shell systems compute isotropic and anisotropic splitting tensors.|
|2||Do not compute tensors.|
Orbital angular momentum analysis.
|1||Yes, do total angular momentum contribution to each MO.|
|10||Report the largest atomic d and f contributions to orbitals specified by IOp(6/84).|
|20||Report the largest transition metal atomic d and f contribs. to orbitals specified by IOp(6/84).|
|30||Read a list of atoms whose d and f contributions will be analyzed.|
|90||Do not do atomic d and f contributions.|
|100||Report the population of each angular momentum on each atom.|
Orbitals to analyze for d and f contributions.
|0||Just occupied orbitals.|
|N||Occupieds plus lowest N virtuals.|
Computation of multipole moments.
|0||Default (1, except for PBC and old semi-empirical).|
|1||Calculate with DipInt.|
|2||Use stored moment operators.|
Thresholds for orbital atomic angular momentum printing.
|NN||At least NN % to print contribution from L on a particular atom.|
Do Natural Transition Orbital Analysis.
|1||Yes, if ground to excited transition density requested.|
|10||Save over canonical MOs.|
Whether to include p’s as valence for transition metals and actinides during NBO analysis.
Whether to compute electron-electron spin-spin coupling.
|1||Yes, if multiplicity >2.|
Thresholds for HLY charge fitting.
|0||Default (Tiny=1.d-8, ThrGrd=1.D-8)|
Reference density for HLY charge fitting.
Sigma parameter for HLY charge fitting.
|1||Yes, with Davidson.|
|2||Yes, with DiagDN.|
Analyze all orbitals by atom and angular momentum contribution.
|-2||Highest 10 occupieds and lowest 10 virtuals.|
|-1||Yes, for all orbitals.|
|N||For highest N occupieds and lowest N virtuals.|
|N||Command N in file 747.|
Which ONIOM system is being done, which is sometimes needed by external procedures.
|2||Model system for 2-layer, middle for 3-layer.|
|3||Small model system for 3-layer.|
Store nuclear repulsion energy as total energy? (Here, store only the nuclear contribution to the dipole moment).
|-1||Same as 0.|
|0||Default to Gau_External.|
|1||Default to runnbo6.|
Whether to compute BEBO energy corrections.
|0||Default (1 if parameters available).|
|10||Use number of pairs (including core) rather than number of lone pairs.|
|20||Use number of lone pairs.|
|1||Do regular calculations.|
Whether to do DCT charge transfer analysis on the selected excited state densities:
|1||Do the analysis if excited state densities are available, and for the relaxed excited state density if this was selected.|
|NNNx||Do a maximum of NNN matrices at a time.|
Last updated on: 30 August 2022. [G16 Rev. C.01]