1%
2% $Id$
3%
4\label{sec:sodft}
5
6
7The spin-orbit DFT module (SODFT) in the NWChem code allows for the variational treatment
8of the one-electron spin-orbit operator within the DFT framework. The implementation
9requires the definition of an effective core potential (ECP) and a matching spin-orbit
10potential (SO). The current implementation does NOT use symmetry.
11
12The actual SODFT calculation will be performed when the input module
13encounters the \verb+TASK+ directive (Section \ref{sec:task}).
14
15\begin{verbatim}
16  TASK SODFT
17\end{verbatim}
18
19Input parameters are the same as for the DFT, see section \ref{sec:dft} for specifications.
20Some of the DFT options are not available in the SODFT. These are \verb+max_ovl+ and
21\verb+sic+.
22
23Besides using the standard ECP and basis sets, see Section \ref{sec:ecp} for details, one
24also has to specify a spin-orbit (SO) potential. The input specification for the SO potential
25can be found in section \ref{sec:spinorb_ecp}. At this time we have not included any spin-orbit
26potentials in the basis set library.
27
28Note: One should use a combination of ECP and SO potentials that were designed for the same
29size core, i.e. don't use a small core ECP potential with a large core SO potential (it will
30produce erroneous results).
31
32Also, note that charge fitting basis sets will not work with
33spin-orbit calculations.
34
35The following is an example of a calculation of $\mathrm{UO_2}$:
36
37\begin{verbatim}
38start uo2_sodft
39echo
40
41Memory 32 mw
42
43charge 2
44
45geometry noautoz noautosym units angstrom
46 U     0.00000      0.00000     0.00000
47 O     0.00000      0.00000     1.68000
48 O     0.00000      0.00000    -1.68000
49end
50
51basis "ao basis" cartesian print
52U    S
53        12.12525300         0.02192100
54         7.16154500        -0.22516000
55         4.77483600         0.56029900
56         2.01169300        -1.07120900
57U    S
58         0.58685200         1.00000000
59U    S
60         0.27911500         1.00000000
61U    S
62         0.06337200         1.00000000
63U    S
64         0.02561100         1.00000000
65U    P
66        17.25477000         0.00139800
67         7.73535600        -0.03334600
68         5.15587800         0.11057800
69         2.24167000        -0.31726800
70U    P
71         0.58185800         1.00000000
72U    P
73         0.26790800         1.00000000
74U    P
75         0.08344200         1.00000000
76U    P
77         0.03213000         1.00000000
78U    D
79         4.84107000         0.00573100
80         2.16016200        -0.05723600
81         0.57563000         0.23882800
82U    D
83         0.27813600         1.00000000
84U    D
85         0.12487900         1.00000000
86U    D
87         0.05154800         1.00000000
88U    F
89         2.43644100         0.35501100
90         1.14468200         0.40084600
91         0.52969300         0.30467900
92U    F
93         0.24059600         1.00000000
94U    F
95         0.10186700         1.00000000
96O    S
97        47.10551800        -0.01440800
98         5.91134600         0.12956800
99         0.97648300        -0.56311800
100O    S
101         0.29607000         1.00000000
102O    P
103        16.69221900         0.04485600
104         3.90070200         0.22261300
105         1.07825300         0.50018800
106O    P
107         0.28418900         1.00000000
108O    P
109         0.07020000         1.00000000
110END
111
112ECP
113U nelec 78
114  U s
115    2          4.06365300        112.92010300
116    2          1.88399500         15.64750000
117    2          0.88656700         -3.68997100
118  U p
119    2          3.98618100        118.75801600
120    2          2.00016000         15.07722800
121    2          0.96084100          0.55672000
122  U d
123    2          4.14797200         60.85589200
124    2          2.23456300         29.28004700
125    2          0.91369500          4.99802900
126  U f
127    2          3.99893800         49.92403500
128    2          1.99884000        -24.67404200
129    2          0.99564100          1.38948000
130O nelec 2
131  O s
132    2         10.44567000         50.77106900
133  O p
134    2         18.04517400         -4.90355100
135  O d
136    2          8.16479800         -3.31212400
137END
138
139SO
140  U p
141  2    3.986181      1.816350
142  2    2.000160     11.543940
143  2    0.960841      0.794644
144  U d
145  2    4.147972      0.353683
146  2    2.234563      3.499282
147  2    0.913695      0.514635
148  U f
149  2    3.998938      4.744214
150  2    1.998840     -5.211731
151  2    0.995641      1.867860
152END
153
154dft
155  mult 1
156  xc hfexch
157  odft
158  grid fine
159  convergence energy 1.000000E-06
160  convergence density 1.000000E-05
161  convergence gradient 1E-05
162  iterations 100
163  mulliken
164end
165
166task sodft
167\end{verbatim}
168