Updated properties section of manual.

doc/user/property.tex

@@ -1,80 +1,73 @@
 %
-% $Id: property.tex,v 1.23 2004-10-29 21:35:21 edo Exp $
+% $Id: property.tex,v 1.24 2004-12-20 20:00:30 bert Exp $
 %
 \label{sec:property}
+
+Properties can be calculated for both the Hartree-Fock and DFT wave 
+functions. The properties that are available are:
+
+\begin{itemize}
+\item Natural bond analysis
+\item Dipole, quadrupole, and octupole moment 
+\item Mulliken population analysis and bond order analysis
+\item Electrostatic potential (diamagnetic shielding) at nuclei 
+\item Electric field and field gradient at nuclei 
+\item Electron and spin density at nuclei 
+\item NMR shielding (GIAO method)
+\item NMR hyperfine coupling (Fermi-Contact and Spin-Dipole expectation values)
+\item NMR indirect spin-spin coupling
+\end{itemize}
+
+The properties module is started when the task directive
+\verb+TASK <theory> property+ is defined in the user input file. The input 
+format has the form:
+
 \begin{verbatim}
   PROPERTY
-    [property name]
+    [property keyword]
     [CENTER ((com || coc || origin || arb <real x y z>) default coc)]
-    [VECTORS ...]
   END
 \end{verbatim}
 
-Calculation of properties is accomplished with \verb+TASK PROPERTY+
-after the completion of an energy (or MP2 gradient) calculation.  The
-following properties can be computed for all wavefunctions that produce
-orbitals, including Hartree-Fock (closed-shell RHF, open-shell ROHF, and
-open-shell UHF), DFT (closed-shell and open-shell spin unrestricted),
-MCSCF (complete active space), and MP2 (closed-shell RHF and open-shell
-UHF).
+Most of the properties can be computed for Hartree-Fock
+(closed-shell RHF, open-shell ROHF, and open-shell UHF), and DFT
+(closed-shell and open-shell spin unrestricted) wavefunctions. The NMR
+chemical shift is limited to closed-shell wave functions, whereas the NMR 
+hyperfine and indirect spin-spin coupling require a UHF or ODFT wave function.
 
-\begin{itemize}
-\item natural bond analysis
-\item dipole moment
-\item quadrupole moment
-\item octupole moment
-\item Mulliken population analysis and bond order analysis
-\item electrostatic potential (diamagnetic shielding) at nuclei 
-\item electric field at nuclei 
-\item electric field gradient at nuclei 
-\item electron and spin density at nuclei 
-\item NMR chemical shifts (GIAO method) only for closed-shell RHF
-\end{itemize}
+\section{Property keywords}
 
-The default molecular orbital file \verb+$file_prefix$.movecs+ is used
-unless a vectors directive (Section \ref{sec:vectors}) is provided.  It is
-therefore only necessary to include a vectors directive if the MO vectors
-to be analyzed are not coming from the default file, e.g., if they have
-been previously redirected, or if MP2 natural orbitals (file extension
-\verb+".mp2nos"+) are being anaylzed.  The MP2 natural orbitals MUST be
-used if the user wants MP2 properties.
+Each property can be requested by defining one of the following keywords:
 
-\section{Subdirectives}
-
-Note that presenting any property input causes all previous property input
-to be ``forgotten'', unlike other NWChem modules.
-
-Each property can be requested by means of a subdirective among the
-subdirectives provided :
-
-\begin{itemize}
-\item {\tt NBOFILE}
-\item {\tt DIPOLE}
-\item {\tt QUADRUPOLE}
-\item {\tt OCTUPOLE}
-\item {\tt MULLIKEN}
-\item {\tt ESP}
-\item {\tt EFIELD}
-\item {\tt EFIELDGRAD}
-\item {\tt ELECTRONDENSITY}
-\item {\tt GIAO}
-\item {\tt ALL}
-\end{itemize}
+\begin{verbatim}
+  NBOFILE
+  DIPOLE
+  QUADRUPOLE
+  OCTUPOLE
+  MULLIKEN
+  ESP
+  EFIELD
+  EFIELDGRAD
+  ELECTRONDENSITY
+  HYPERFINE
+  SHIELDING [<integer> number_of_atoms <integer> atom_list]
+  SPINSPIN [<integer> number_of_pairs <integer> pair_list]
+  ALL
+\end{verbatim}
 
 The ``{\tt ALL}'' keyword generates all currently available properties. 
 
-The request {\tt NBOFILE} does not execute the Natural Bond Analysis
-code, but simply creates an input file to be used as input to the
-stand-alone NBO code.  All other properties are calculated upon
-request.
+Both the NMR shielding and spin-spin coupling have additional optional
+parameters that can be defined in the input. For the shielding the user
+can define the number of atoms for which the shielding tensor should be 
+calculated, followed by the list of specific atom centers. In the case 
+of spin-spin coupling the number of atom pairs, followed by the atom
+pairs, can be defined (i.e., spinspin 1 1 2 will calculate the coupling 
+for one pair, and the coupling will be between atoms 1 and 2).
 
-An additional subdirective is provided to specify the origin of the
-molecular orbitals used in the calculation of the molecular
-properties. This is the `{\tt VECTORS}' subdirective, also used in the
-SCF and DFT tasks. For a full description of this subdirective
-the user is refered to the description found in the SCF description.
-By default, the input file used for the calculation of the properties
-has the \verb+.movecs+ name extension. 
+For both the NMR spin-spin and hyperfine coupling the isotope that has 
+the highest abundance and has spin, will be choosen for each atom under
+consideration.
 
 The user also has the option to choose the center of expansion for
 the dipole, quadrupole, and octupole calculations.
@@ -92,14 +85,18 @@ must be given in the same units as \verb+UNITS+ in \verb+GEOMETRY+ (See Section
 \subsection{Nbofile}
 \label{sec:Nbofile}
 
+The keyword {\tt NBOFILE} does not execute the Natural Bond Analysis
+code, but simply creates an input file to be used as input to the
+stand-alone NBO code.  All other properties are calculated upon
+request.
+
 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 \verb+TASK+ as \verb+PROPERTY+ and
-supply the sub-directive \verb+NBOFILE+ to the \verb+PROPERTY+ directive.  NWChem
-will query the rtdb and construct an ASCII file,
+by providing the keyword \verb+NBOFILE+ in the \verb+PROPERTY+ directive.  
+NWChem will query the rtdb and construct an ASCII file,
 \verb+<file_prefix>.gen+, that may be used as input to the stand alone
 version of the NBO program, gennbo.  \verb+<file_prefix>+ is equal to
-string following the \verb+RESTART+ directive.  The input deck may be edited
+string following the \verb+START+ directive.  The input deck may be edited
 to provide additional options to the NBO calculation, (see the NBO
 user's manual for details.)