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latest fixes and tweaks, including new example for multiple charge directives, revisions to driver documentation, syntax changes to argos documentation

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Robert Harrison 1997-02-26 03:17:27 +00:00
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8
doc/user/ccsd.tex
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@ -109,10 +109,10 @@ include the directive
TASK CCSD+T(CCSD)
\end{verbatim}
Lower-level results which come as by-products of the requested
calculation are generally also printed in the output file and stored
on the run-time database, but the method specified in the \verb+TASK+
directive is considered the primary result.
Lower-level results which come as by-products (such as MP3/MP4) of the
requested calculation are generally also printed in the output file
and stored on the run-time database, but the method specified in the
\verb+TASK+ directive is considered the primary result.
\section{Debugging and Development Aids}

26
doc/user/dft.tex
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@ -17,30 +17,18 @@ The formal scaling of the DFT computation can be reduced by choosing
to use auxiliary gaussian basis sets to fit the charge density (CD) and/or
fit the exchange-correlation (XC) potential.
The DFT module is invoked in NWChem
by specifying the keyword \verb+dft+ as a TASK directive, e.g.,
\begin{verbatim}
TASK DFT
\end{verbatim}
The keyword \verb+dft+ tells the code that this is a compound directive
potentially containing input for the DFT module. Additional subdirectives
may be specified by the user to define a particular
problem. The \verb+dft+ input will be processed until the
\verb+END+ directive is encountered.
DFT input is provided using the compound \verb+DFT+ directive
\begin{verbatim}
DFT
...
END
\end{verbatim}
The actual DFT calculation will
be performed when the input module encounters the \verb+TASK+ directive.
Refer to the \verb+TASK+ directive description in
Section \ref{sec:task} for a complete list of operations that can be
specified in the DFT module.
The actual DFT calculation will be performed when the input module
encounters the \verb+TASK+ directive (Section \ref{sec:task}).
\begin{verbatim}
TASK DFT
\end{verbatim}
Once a user has specified a geometry and a Kohn-Sham orbital basis set
the DFT module can be invoked with no input directives (defaults
@ -643,7 +631,7 @@ would be interpreted as 80 radial points, 20 theta points, and 40
phi points per center (or 64000 points per center before pruning).
A second quadrature available for the numerical integration is an
Euler-MacLaurin scheme for the radial components and a Lebedev
Euler-Mac\-Laurin scheme for the radial components and a Lebedev
scheme for the angular components\footnote{The subroutine
for the Lebedev grid was supplied by M.~Caus\`a of the University of
Torino.}. Within this numerical integration procedure various levels

74
doc/user/driver.tex
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@ -1,34 +1,38 @@
\label{sec:driver}
The DRIVER module is one of two drivers to perform a geometry
optimization function on the molecule defined by input using the
\verb+GEOMETRY+ directive (see Section \ref{sec:geom}). Geometry
optimization is either an energy minimization or a transition state
optimization. DRIVER is selected by default out of the two available
modules to perform geometry optimization. Selection of the other
optimization driver STEPPER may be made through the use of a SET
directive : ( SET OPT:DRIVER F ) . Optional input for this module is
specified within the compound directive,
The DRIVER module is one of two drivers (see Section \ref{sec:stepper}
for documentation on STEPPER) to perform a geometry optimization
function on the molecule defined by input using the \verb+GEOMETRY+
directive (see Section \ref{sec:geom}). Geometry optimization is
either an energy minimization or a transition state optimization.
The algorithm programmed in DRIVER is a quasi-newton optimization
with line searches and approximate energy hessian updates.
DRIVER is selected by default out of the two available modules to
perform geometry optimization. In order to force use of DRIVER (e.g.,
because a previous optimization used STEPPER) provide a DRIVER input
block (below) --- even an empty block will force use of DRIVER.
Optional input for this module is specified within the compound
directive,
\begin{verbatim}
DRIVER
...
END
\end{verbatim}
The algorithm programmed in DRIVER is a quasi-newton optimization
with line searches and approximate energy hessian updates.
Input specified for the DRIVER module may appear anywhere in the input
file. In the current version of NWChem, DRIVER uses geometries that
are defined via Cartesian coordinates or internal coordinates. The
latter may be user-defined with the ZMT input or may be automatically
defined as a result of the AUTOZ option. The initial guess nuclear
Hessian is the identity matrix and there is an ASCII interface file to
input a Hessian from another code. The automatic generation of finite
difference Hessians will be available soon. When internal coordinates
are selected an appropriate initial hessian matrix is automatically
created to match the internal coordinate definition.
file preceding the \verb+TASK+ directive performing the optimization.
In the current version of NWChem, DRIVER uses geometries that are
defined via Cartesian coordinates or internal coordinates. The latter
may be user-defined with the Z-matrix input (Section
\ref{sec:Z-matrix}) or may be automatically generated using the
\verb+AUTOZ+ option (Section \ref{sec:geomkeys}). The initial guess
nuclear Hessian is the identity matrix and there is an ASCII interface
file to input a Hessian from another code. The automatic generation
of finite difference Hessians will be available soon. When internal
coordinates are selected an appropriate initial hessian matrix is
automatically created to match the internal coordinate definition.
Execution of the DRIVER module calculation is invoked with a
\verb+TASK+ directive (see Section \ref{sec:task}).
@ -37,29 +41,37 @@ No input is required for DRIVER. If no input is present the default
actions are to minimize the energy as a function of the geometry with a
maximum of 20 stepper iterations.
\section{{\tt NTPOPT} --- Maximum number of steps}
\begin{verbatim}
NTPOPT <integer nptopt default 20>
\end{verbatim}
The value specified for the integer \verb+ntpopt+ defines the maximum
The value specified for the integer \verb+<ntpopt>+ defines the maximum
number of geometry optimization steps.
\section{{\tt CVGOPT} --- Convergence criterion}
\begin{verbatim}
CVGOPT <real cvgopt default 0.0008>
\end{verbatim}
The value specified for the real \verb+cvgopt+ defines the convergence
The value specified for the real \verb+<cvgopt>+ defines the convergence
threshold of the optimization algorithm. The convergence criterion is
the largest component of the energy gradient for the coordinates used
in the optimization ( cartesian or internal coordinates ).
\section{{\tt LINOPT} --- Linear search}
\begin{verbatim}
LINOPT <integer linopt default 10>
\end{verbatim}
The value specified for the integer \verb+linopt+ defines the maximum
The value specified for the integer \verb+<linopt>+ defines the maximum
number of energy points during any linear search.
\section{{\tt INHESS} and {\tt MODUPD} --- Hessian update algorithm}
\begin{verbatim}
INHESS <integer inhess default 0>
\end{verbatim}
@ -68,18 +80,22 @@ number of energy points during any linear search.
MODUPD <integer modupt default 1>
\end{verbatim}
The value specified for the integer \verb+modupd+ defines the hessian
update algorithm, Fletcher-Powell update ( modupd 0 ) or
Broyden-Fletcher-Goldfar-Shanno update ( modupd 1 )
The value specified for the integer \verb+<modupd>+ defines the hessian
update algorithm, Fletcher-Powell update (\verb+<modupd> = 0+) or
Broyden-Fletcher-Goldfar-Shanno update (\verb+<modupd> = 1+)
\section{{\tt MODSAD} --- Optimization mode}
\begin{verbatim}
MODSAD <integer modsad default 0>
\end{verbatim}
The value specified for the integer \verb+modsad+ defines the type
of optimization to be performed, an energy minimization ( modsad 0 )
or a transition state optimization ( modsad 1 ).
of optimization to be performed, an energy minimization
(\verb+<modsad> = 0+)
or a transition state optimization (\verb+<modsad> = 1+).
\section{{\tt MODDIR} --- Normal mode selection}
\begin{verbatim}
MODDIR <integer moddir default 1>

11
doc/user/functionality.tex
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@ -30,6 +30,8 @@ For all methods, the following operations may be performed
\begin{itemize}
\item Single point energy.
\item Geometry Optimization (Minimization and Transition State).
\item Molecular dynamics on the fully {\em ab initio} potential energy
surface.
\item Numerical first and second derivatives automatically computed if
analytic derivatives are not available.
\item Generation of the electron density file for the {\em Insight}
@ -59,4 +61,13 @@ simulations
\item Free energy simulation
\end{itemize}
There is also the capability to combine classical and quantum
descriptions in order to perform
\begin{itemize}
\item Mixed quantum-mechanics and molecular-mechanics (QM/MM)
minimizations and molecular dynamics using any of the quantum
mechanical wavefunctions.
\end{itemize}

76
doc/user/geometry.tex
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@ -59,6 +59,7 @@ keywords in each of the three main parts.
% These are examined in the following sections.
\section{Main keywords on the {\tt GEOMETRY} directive}
\label{sec:geomkeys}
This section presents the options that can be specified using the keywords
and optional input on the main line of the {\tt GEOMETRY} directive.
@ -248,19 +249,20 @@ usage and definitions of the values specified for the variable \verb+<tag>+
to describe the centers in a system;
\begin{itemize}
\item If the tag begins with characters that cannot be
matched against an atom, and those characters are not \verb+BQ+
or \verb+X+, then a fatal
error is generated.
\item The tag of a center is used in the \verb+BASIS+ directive (Section
\ref{sec:basis}) to associate functions with centers.
matched against an atom, and those characters are not \verb+BQ+
or \verb+X+, then a fatal
error is generated.
\item The tag of a center is used in the \verb+BASIS+ (Section
\ref{sec:basis}) and \verb+ECP+ (Section \ref{sec:ecp}) directives
to associate functions with centers.
\item All centers with the same tag will have the same basis
functions.
functions.
\item When automatic symmetry detection is functional, only centers
with the same tag will be candidates for testing for symmetry
equivalence.
with the same tag will be candidates for testing for symmetry
equivalence.
\item The user specified charges (of all centers, atomic and dummy)
and any net total charge of the system (Section \ref{sec:charge}) are
used to determine the number of electrons.
and any net total charge of the system (Section \ref{sec:charge}) are
used to determine the number of electrons.
\end{itemize}
The Cartesian coordinates of the atom in the molecule are specified as
@ -528,9 +530,9 @@ geometry
CF2 1.3669
CF3 1.3669
constants
HCH1 10428
HCH2 10474
HCH3 1047
HCH1 104.28
HCH2 104.74
HCH3 104.7
CCF1 112.0713
CCF2 112.0341
CCF3 112.0340
@ -562,40 +564,28 @@ internal coordinates. These are arranged as follows:
\section{{\tt ZCOORD} --- Forcing internal coordinates}
\label{sec:zcoord}
Specifying the keyword \verb+AUTOZ+ on the first line of the \verb+GEOMETRY+
directive forces automatic generation of internal
coordinates for use in geometry optimizations. Connectivity
is inferred by comparing inter-atomic distances with van de Waals
radii, and under some circumstances it may be necessary to augment the
Specifying the keyword \verb+AUTOZ+ on the first line of the
\verb+GEOMETRY+ directive forces automatic generation of internal
coordinates for use in geometry optimizations. Connectivity is
inferred by comparing inter-atomic distances with van de Waals radii,
and under some circumstances it may be necessary to augment the
automatically generated list of internal coordinates. This is
accomplished by including the optional directive {\tt ZCOORD} within the geometry
directive. The general form of the \verb+ZCOORD+ directive is as follows,
accomplished by including the optional directive {\tt ZCOORD} within
the geometry directive. The general form of the \verb+ZCOORD+
directive is as follows,
\begin{verbatim}
[ZCOORD
<ij_flag> <list_of_z-coordinate_variables>
...
END]
ZCOORD
[ijbond <integer i> <integer j>]
[ijkang <integer i> <integer j> <integer k>]
[ijklto <integer i> <integer j> <integer k> <integer l>]
[ijklop <integer i> <integer j> <integer k> <integer l>]
[ijklnb <integer i> <integer j> <integer k> <integer l>]
END
\end{verbatim}
% The centers \verb+i+, \verb+j+, \verb+k+ and \verb+l+ below {\em must} be
% specified using number of the centers.
The specific input that must be supplied for the \verb+i+, \verb+j+, \verb+k+, and
\verb+l+ is described below. The centers
\verb+i+, \verb+j+, \verb+k+ and \verb+l+ are numbered automatically in the
order they are supplied on the input for the \verb+ZMATRIX+ directive. The
user must adhere to this convention when suppliying the \verb+ZCOORD+
directive input described here. The bond length and angles for the centers
are defined as follows;
\begin{verbatim}
ZCOORD
ijbond i j
ijkang i j k
ijklto i j k l
ijklop i j k l
ijklnb i j k l
END
\end{verbatim}
The centers \verb+i+, \verb+j+, \verb+k+ and \verb+l+ {\em must}
be specified using the number of the centers as supplied in the input
for the \verb+ZMATRIX+ directive.
\begin{itemize}
\item {\tt ijbond} --- a bond between the two centers.

40
doc/user/getstart.tex
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@ -199,11 +199,6 @@ scf
print low
end
stepper
trust 0.5
convgg 0.01
end
set "ao basis" "starting basis"
task scf optimize
@ -217,10 +212,6 @@ end
set "mp2_grad:print" low
stepper
convgg 1d-6
end
task mp2 optimize
set "mp2_grad:print" none
@ -265,14 +256,6 @@ available for open-shell systems currently (see Section
reduce the output from the SCF module to a minimum during the geometry
optimization.
For this calculation, the gradient convergence threshold for the
geometry optimization module {\tt STEPPER} is set to the
relaxed value of $10^{-2}$, rather than the default $10^{-4}$. This is
acceptable because the initial optimization only serves to provide a
starting guess. Increasing the trust radius (using the \verb+TRUST+
directive) beyond the default of $0.1$ makes the optimization more
efficient (though less robust in hard to converge cases).
The final step in setting up the input for the SCF calculation is to
specify that the \verb+"starting basis"+ should be used. This is
accomplished by means of the \verb+SET+ directive, which specifies that
@ -312,19 +295,8 @@ guess vectors are reset to be the atomic guess, since the STO3G
vectors are not appropriate (see Section \ref{sec:vectors} for
details on the different possible starting guesses).
The convergence threshold for the geometry optimization module is reset
to $10^{-6}$ for the second task, a value which is smaller than
the default of $10^{-4}$. The default is appropriate for determination of the
optimized geometry and minimum energy, but a higher accuracy is
required in this task, for use in the subsequent computation of the
frequencies. The second {\tt TASK} directive invokes an MP2
optimization, instead of the SCF optimization.
% There is currently no input block for the MP2 gradients, so parameters
% for this module have to be set in the database via the {\tt set}
% directive. Currently only print options are recognized, and in this
% example, the \verb+SET+ directive is used to reduce the amount of
% output a reasonable minimum.
The second {\tt TASK} directive invokes an MP2 optimization, instead
of the SCF optimization.
Once the MP2 optimization is completed, the geometry obtained in the
calculation is used to perform a frequency calculation. This task is
@ -402,6 +374,8 @@ other.
The following notation and syntax conventions are used in the generic
descriptions of the NWChem input in the following sections.
\sloppy
\begin{itemize}
\item a directive name always appears in all-capitals, in computer-type
face; (e.g.; \verb+GEOMETRY+, \verb+BASIS+, \verb+SCF+). Note that
@ -437,6 +411,8 @@ characters following \verb+#+ (up to the physical end of the line) are ignored.
\item \verb+...+ is used to indicate indefinite continuation of a list
\end{itemize}
\fussy
An input parameter is identified in the description of the directive
by prefacing the item with the name of the type of data expected;
i.e.,
@ -446,12 +422,12 @@ i.e.,
\item \verb+integer+ -- integer value(s) for a variable or an array
\item \verb+logical+ -- true/false logical variable
\item \verb+real + -- real floating point value(s) for a variable or
\item \verb+double + -- double-precision
\item \verb+double + -- synonymous with real
an array
\end{itemize}
If an input item is not prefaced by one of these type names,
it is assumed to be of type 'string'.
it is assumed to be of type ``string''.
The directive \verb+VECTORS+ (Section \ref{sec:vectors}) is presented here
as an example of an NWChem input directive. The general form of the

20
doc/user/intro.tex
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@ -75,8 +75,11 @@ including;
\begin{itemize}
\item detailed description of problem
\item platform you are running on
\item site name (e.g., EMSL, NERSC, \ldots)
\item platform you are running on including
\begin{itemize}
\item vendor name
\item computer model
\item operating system
\item compiler
\end{itemize}
@ -92,16 +95,13 @@ with the code and discuss problems. Announcements of new releases and
bug fixes will also be made to this list.
To subscribe to the user list, send a message to
\begin{itemize}
\item {\tt majordomo@emsl.pnl.gov}
\end{itemize}
\begin{verbatim}
majordomo@emsl.pnl.gov
\end{verbatim}
The body of the message must contain the line
\begin{itemize}
\item {\tt subscribe nwchem-users}
\end{itemize}
\begin{verbatim}
subscribe nwchem-users
\end{verbatim}
The automated list manager is capable of recognizing a number of
commands, including 'subscribe', 'unsubscribe', 'get', 'index',

19
doc/user/nwarch.tex
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@ -68,10 +68,9 @@ Objects are built in the database by storing associated data as
multiple entries using an internally consistent naming convention.
This data is exclusively managed by the subroutines (or methods) that
are associated with the object. Currently, the code has two main
objects; basis sets and geometries. Sections \ref{sec:geom},
\ref{sec:basis}, and
\ref{sec:ecp} present a complete discussion of the input to describe
these objects.
objects; basis sets and geometries. Sections \ref{sec:geom} and
\ref{sec:basis}present a complete discussion of the input to describe
these objects.
As an illustration of what comprises a geometry object, the following
table contains a partial listing of the NWChem output of a water molecule
@ -101,12 +100,6 @@ for the water molecule, for example, an input file could be constructed with
all of the geometries of interest by storing them in the
database under different names.
% The {\tt
% GEOMETRY} directive (Section \ref{sec:geom}) permits geometries to
% be named (the default name is \verb+geometry+). For example, the
% input directive to define a geometry object in the database with the
% name \verb+"test water geometry"+ can be specified as follows;
The run-time database contents for the file \verb+h2o.db+ listed
above were generated from the user-specified input directive,
\begin{verbatim}
@ -146,12 +139,6 @@ NWChem will automatically check for such indirections when loading
geometries. The basis set object functions in an identical fashion,
using the default name \verb+"ao basis"+.
% , and it is intended that all
% future such objects will do so. (Note: the naming conventions and
% internal mechanisms for associating data with specific modules or
% tasks is expected to change in the future, but the directive for
% specifying names should remain the same.)
\section{Persistence of data and restart}
\label{sec:persist}

538
doc/user/nwargos.tex
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File diff suppressed because it is too large Load diff

35
doc/user/property.tex
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@ -7,26 +7,24 @@
The following properties can be extracted from the wavefunction.
dipole moment
quadrupole moment
octupole moment
Mulliken population analysis and bond order analysis
electrostatic potential ( diamagnetic shielding ) at nuclei + grid
electric field at nuclei + grid
electric field gradient at nuclei + grid
electron density and electron wavefunction at nuclei + grid
Boy's localized orbitals
spin density
Stone's distributed multipole analysis
static dipole polarizabilities and hyperpolarizabilities
dynamic dipole polarizabilitites and hyperpolarizabilities
natural bond analysis
\begin{itemize}
\item dipole moment
\item quadrupole moment
\item octupole moment
\item Mulliken population analysis and bond order analysis
\item electrostatic potential (diamagnetic shielding) at nuclei and grid
\item electric field at nuclei and grid
\item electric field gradient at nuclei and grid
\item electron density and electron wavefunction at nuclei and grid
\item Boy's localized orbitals
\item spin density
\item Stone's distributed multipole analysis
\item static dipole polarizabilities
\item natural bond analysis
\end{itemize}
\subsection{nbofile}
=======
\section{nbofile}
Following the successful completion of an electronic structure
calculation, a Natural Bond Orbital (NBO) analysis may be carried out
in the following way. On restart specify the TASK as PROPERTY and
@ -37,3 +35,4 @@ version of the NBO program, gennbo. \verb+<file_prefix>+ is equal to
string following the RESTART directive. The input deck may be edited
to provide additional options to the NBO calculation, (see the NBO
user's manual for details.)

27
doc/user/scf.tex
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@ -318,10 +318,14 @@ those centers. Two parameters must be set as follows:
set atomscf:z <real list_of_charges>
\end{verbatim}
The arrary of strings \verb+atomscf:tags_z+ should be set to the list
of tags and array \verb+atomscf:z+ should be set to the list of tags.
All atoms that have the same tag as one specified in this list will be
assigned the corresponding charge.
\sloppy
The array of strings \verb+atomscf:tags_z+ should be set to the list
of tags, and the array \verb+atomscf:z+ should be set to the list of
charges. All atoms that have the same tag as one specified in this
list will be assigned the corresponding charge.
\fussy
For example, the following specifies that all oxygen atoms with tag
\verb+O+ be assigned a charge of \verb+-1+ and all iron atoms with tag
@ -412,7 +416,7 @@ V-approximation of Alml\"{o}f and Vahtras) is automatically invoked if
a basis set named \verb+"riscf basis"+ is present in the database.
This basis will be used as the fitting basis. The RI-SCF method
provides most computational speedup with least loss of accuracy when
applied to relatively small molecules in larage basis sets.
applied to relatively small molecules in large basis sets.
Calculations on large molecules in modest basis sets will not realize
a significant performance gain from RISCF.
@ -610,12 +614,13 @@ If integrals are stored with a threshold of greater than $10^{-10}$,
then the integrals themselves are stored in a 32-bit fixed-point
format (with special treatment for large values to retain precision).
If integrals are stored with a threshold that is less than $10^{-10}$,
howwever, the values are stored in 64-bit floating-point format. If a
however, the values are stored in 64-bit floating-point format. If a
replicated-data calculation is being run, then 8 bits are used for
each basis function label, unless there are more than 256 functions,
in which case 16 bits are used. If distributed-data is being used,
then the labels are always packed to 8-bits (the distributed blocks
always being less than 256).
always being less than 256 and labels are relative to the start of the
block).
Thus, the number ($W$) of 64-bit words required to store $N$
integrals, may be computed as
@ -681,10 +686,10 @@ This information may be used to optimize subsequent calculations.
{\em Note to users:} It is desired that the SCF program converge
reliably with the default options for a wide variety of molecules. In
addition it should be guaranteed to converge sufficient iterations for
any system. Please report significant convergence problems to
\verb+nwchem+-\verb+support@+\-\verb+emsl.pnl.gov+, including the
input file.
addition, it should be guaranteed to converge sufficient with
iterations for any system. Please report significant convergence
problems to \verb+nwchem+-\verb+support@+\-\verb+emsl.pnl.gov+,
including the input file.
% An understanding of the output of the SCF program and the options
% controlling convergence requires some knowledge of the convergence

59
doc/user/top-level.tex
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@ -46,7 +46,7 @@ prefix. That is, the variable {\tt <file\_prefix>} is assigned
the name of the input file, with any directory
information and the last "dot-prefix" removed. For example,
the input file
name \verb+/home/dave/job.2.in+ yields \verb+job.2+ as the file
name \verb+/home/dave/job.2.nw+ yields \verb+job.2+ as the file
prefix, if a name is not assigned explicitly using the \verb+START+
directive.
@ -174,9 +174,10 @@ following steps in order;
\item Look for a directory qualified by the process number of the
invoking process.
\item If there is a list of directories qualified by the name of the
host machine (as returned by \verb+util_hostname()+), then use
round-robin allocation from the list for processes executing on the
given host.
host machine\footnote{As returned by {\tt util\_hostname()} which
maps to the output of the command {\tt hostname} on Unix
workstations.}, then use round-robin allocation from the list for
processes executing on the given host.
\item If there is a list of directories unqualified by any hostname
or process ID, then use round-robin allocation from this list.
\end{enumerate}
@ -631,15 +632,14 @@ database is persistent, multiple tasks within one job behave {\em
exactly} the same as multiple restart jobs with the same sequence of
input.
There are three main forms of the the \verb+TASK+ directive. One form is
used to tell the code when to execute most of the electronic structure
and molecular dynamics
calculations. The second form is used to specify tasks such as
printing the contents of the database, or simple property
evaluations. The third form is used to execute UNIX commands on machines
having a Bourne shell. Additional forms will be added in the near
future to accomodate mixed molecular-mechanics and quantum-mechanics
(MM/QM) calculations.
There are three main forms of the the \verb+TASK+ directive. One form
is used to tell the code when to execute most of the electronic
structure and molecular dynamics calculations. The second form is
used to specify tasks such as printing the contents of the database,
or simple property evaluations. The third form is used to execute
UNIX commands on machines having a Bourne shell. Additional forms
will be added in the near future to accomodate mixed quantum-mechanics
and molecular-mechanics (QM/MM) calculations.
By default, the program terminates when a task does not complete
successfully. The keyword \verb+ignore+ can be used to prevent this,
@ -732,8 +732,8 @@ theory, the \verb+TASK+ directive is
task dft optimize
\end{verbatim}
The keyword \verb+ignore+ allows execution to continue even if the
task fails, as discussed above.
The optional keyword \verb+ignore+ can be used to allow execution to
continue even if the task fails, as discussed above.
\subsection{{\tt TASK} Directive for Special Operations}
@ -778,7 +778,9 @@ that the given command will be executed in the Bourne shell. The user
can also specify which process(es) will execute this command by
entering values for \verb+processor+ on the directive. The default is
for only process zero to execute the command. A range of processors
may be specified, using Fortran triplet notation. Alternatively, all
may be specified, using Fortran triplet notation\footnote{The notation
\verb+lo:hi:inc+ denotes the integers \verb+lo+, \verb=lo+inc=,
\verb=lo+2*inc=, \ldots, \verb+hi+}. Alternatively, all
processes can be specified simply by entering the keyword \verb+all+.
The input entered for \verb+command+ must form a single string, and
consist of valid UNIX command(s). If the string includes white space,
@ -837,5 +839,30 @@ If centers with fractional charge have been specified (Section
\ref{sec:geom}) the net charge of the system should be adjusted to
ensure that there is an integral number of electrons.
The charge may be changed between tasks and is used by all
wavefunction types. For instance, in order to compute the first two
vertical ionization energies of $LiH$ one might optimize the geometry
of $LiH$ using a UHF SCF wavefunction and then perform energy
calculations at the optimized geometry in turn on $LiH^+$ and
$LiH^{2+}$. This is accomplished with the following input.
\begin{verbatim}
geometry; Li 0 0 0; H 0 0 1.64; end
basis; Li library 3-21g; H library 3-21g; end
scf; uhf; singlet; end
task scf optimize
charge 1
scf; uhf; doublet; end
task scf
charge 2
scf; uhf; singlet; end
task scf
\end{verbatim}
The \verb+GEOMETRY+, \verb+BASIS+, and \verb+SCF+ directives are
described below (Sections \ref{sec:geom}, \ref{sec:basis} and
\ref{sec:scf} respectively) but their intent should be clear. The
\verb+TASK+ directive is described above (Section \ref{sec:task}).

31
doc/user/user.tex
View file

@ -1,4 +1,4 @@
% $Id: user.tex,v 1.17 1997-02-25 20:34:49 d3g681 Exp $
% $Id: user.tex,v 1.18 1997-02-26 03:17:27 d3g681 Exp $
\documentstyle[fullpage,12pt]{book}
\setlength{\parskip}{6pt}
@ -60,21 +60,9 @@
\chapter{Gaussian Density Functional Theory (DFT)}
\input{dft.tex}
\chapter{Geometry Optimization with STEPPER}
\input{stepper}
\chapter{Vibrational frequencies}
\input{vib}
\chapter{MP2}
\input{mp2}
\chapter{Four-Index Transformation}
\input{fourindex}
\chapter{Plane-wave periodic DFT}
\input{plnwv.tex}
\chapter{Multiconfiguration SCF}
\input{mcscf.tex}
@ -84,6 +72,21 @@
\chapter{Coupled Cluster Calculations}
\input{ccsd.tex}
\chapter{Four-Index Transformation}
\input{fourindex}
\chapter{Plane-wave periodic DFT}
\input{plnwv.tex}
\chapter{Geometry Optimization with DRIVER}
\input{driver}
\chapter{Geometry Optimization with STEPPER}
\input{stepper}
\chapter{Vibrational frequencies}
\input{vib}
\chapter{DPLOT}
\input{dplot.tex}
@ -93,7 +96,7 @@
\chapter{Molecular Dynamics}
\input{nwargos.tex}
\chapter{Combined Quantum Mechanics and Molecular Mechanics}
\chapter{Combined Quantum and Molecular Mechanics}
\input{qmmm}
\clearpage