MRSF TDDFT Energy calculation log file - Open-Quantum-Platform/openqp GitHub Wiki
The OQP log file starts with the started time of the job and a quick introduction to main developers and the how may CPU cores chosen for the job.
2 PyOQP started at 2024-03-25 14:08:07
3
4
5 ***********************************************************
6 * *
7 * Open Quantum Platform *
8 * *
9 ***********************************************************
10 * *
11 * OQP was initiated by Prof. Cheol Ho Choi on 2012. *
12 * *
13 * After that, it has been mostly developed by *
14 * Dr. Vladimir Mironov, *
15 * Dr. Hiroya Nakata, *
16 * Mr. Igor Gerasimov, *
17 * and Dr. Konstantin Komarov. *
18 * *
19 * On 2024, Prof. Jingbai Li at Hoffmann Institute of *
20 * Advanced Materials has started to develop pyOQP. *
21 * *
22 ***********************************************************
23
24 Job starts at Mon Mar 25 14:08:07 2024
25 on the host of chc2.knu.ac.kr
26 with 88 CPU cores.
After that OQP will read every single section in your job's input file and sets things up.
28 ++++++++++++++++++++++++++++++++++++++++
29 MODULE: apply_basis
30 Setting up basis set information
31 ++++++++++++++++++++++++++++++++++++++++
32
33 Basis Sets options
34 ------------------
35 Basis Set File: /bighome/ali/modules/share/basis_sets/6-31gs.bas
36 Number of Shells = 10 Number of Primitives = 23
37 Number of Basis Set functions = 19
38 Maximum Angluar Momentum = 3
39
40
41 ++++++++++++++++++++++++++++++++++++++++
42 MODULE: HSandT
43 Computing H, S and T Matrices
44 ++++++++++++++++++++++++++++++++++++++++
45
46 ================================
47 Cartesian Coordinate in Angstrom
48 ================================
49 ATOM ZNUC X Y Z
50 --------------------------------------------------------------
51 1 8.0 0.000000000 0.000000000 -0.041061554
52 2 1.0 -0.533194329 0.533194329 -0.614469223
53 3 1.0 0.533194329 -0.533194329 -0.614469223
54
55 ...... End Of One Electron Integrals ......
56
57
58 ++++++++++++++++++++++++++++++++++++++++
59 MODULE: Guess_Huckel
60 Initial guess using Huckel theory
61 ++++++++++++++++++++++++++++++++++++++++
62
63 ...... End of initial orbital guess ......
64
65 Step CPU time in seconds = 0.0 wall time in seconds = 0.0
66 Total CPU time in seconds = 0.0 wall time in seconds = 0.0
67
68 ==============================================
69 PyQOP: Orbital Guess
70 ==============================================
71
72 PyOQP guess type: huckel
73 PyOQP guess file: compute orbitals
74 PyOQP guess alpha: computed
75 PyOQP guess beta: computed
76
77
78 ==============================================
79 PyOQP: Entering Electronic Energy Calculation
80 ==============================================
81
82 PyOQP natom: 3
83 PyOQP charge: 0
84 PyOQP basis: 6-31gs
85
86
87 ==============================================
88 PyOQP: Normal SCF steps
89 ==============================================
90
91 PyOQP method: tdhf
92 PyOQP hf/functional: bhhlyp
93 PyOQP scf type: rohf
94 PyOQP scf maxit: 30
95 PyOQP scf multiplicity: 3
96 PyOQP scf convergence: 1e-06
97 PyOQP scf incremental: True
98
99
100 ++++++++++++++++++++++++++++++++++++++++
101 MODULE: HF_DFT_Energy
102 Computing HF/DFT SCF Energy
103 ++++++++++++++++++++++++++++++++++++++++
104
105 Standard Grid 1 (SG1)
106 ---------------------
107 XC functional: BHHLYP
108 THRESH= 0.00E+00
109
110 The LibXC 5.1.7 version is used!
After OQP read all of the sections in your input file, it will start the SCF procedure. but before that you have to pay attention that when you use the LibXC, you have to cite this papers:
112 THE FOLLOWING PAPERS SHOULD BE CITED WHEN USING LIBXC INTERFACE:
113 S. Lehtola, C. Steigemann, M. J. Oliveira, and M. A. Marques, SoftwareX 7, 1 (2018)
114 DOI: 10.1016/j.softx.2017.11.002
115 and
116 Igor S. Gerasimov, Federico Zahariev, Sarom S. Leang, Anton Tesliuk, Mark S. Gordon, Michael G. Medvedev,
117 Introducing LibXC into GAMESS (US),
118 Mendeleev Commun., 2021, 31, 302–305
119 DOI: 10.1016/j.mencom.2021.05.008
120
121 The information about selected functionals:
122 The BHandHLYP exchange-correlation functional will be used with a coefficient 1.00000000E+00.
123 The functional has been described in the following articles:
124 [1] A. D. Becke, J. Chem. Phys. 98, 1372 (1993); DOI: 10.1063/1.464304
125 [2] Defined through Gaussian implementation;
In the next part OQP will set up the given functional:
127 The global hybrid part: 5.00000000E-01
128
129 DFT Threshold = 0.179E-07
130 Radial quadrature: 96 points
131 Smallest Gaussian primitive exponent= 0.1612777588 of type -S-
132 on atom number 2 has radial normalization= 1.000000
133 Largest Gaussian primitive exponent= 5484.6716600000 of type -S-
134 on atom number 1 has radial normalization= 1.000000
135 Step CPU time in seconds = 4.5 wall time in seconds = 0.1
136 Total CPU time in seconds = 4.5 wall time in seconds = 0.1
137
Global Hybrid Part: 0.50000000: This refers to the mixing parameter in hybrid Density Functional Theory (DFT) calculations. Hybrid functionals are a class of approximations used in DFT to include a portion of exact exchange from Hartree-Fock theory with the rest from DFT exchange-correlation functionals. A value of 0.5 means that 50% of the exchange is coming from the exact Hartree-Fock method, and the rest is from DFT. This is typical of hybrid functionals like BHHLYP.
DFT Threshold = 0.179E-07: This threshold indicates the convergence criterion for the self-consistent field (SCF) procedure in DFT calculations. A smaller threshold means more accurate results but requires more computational time. The value 0.179E-07 suggests that the calculations are stopped when changes in the electron density between iterations fall below this value.
Radial quadrature: 96 points: In DFT, integrals over electron density are evaluated numerically. Radial quadrature points refer to the number of points used in the numerical integration over the radial coordinate. Here, 96 points indicate the level of discretization and directly impact the accuracy and computational cost of the calculation.
Gaussian Primitive Exponents
- Smallest/Largest Gaussian primitive exponent: Gaussian primitives are functions used in the basis set for molecular orbital calculations. The exponents determine how spread out or contracted these functions are.
- _The smallest exponent (0.1612777588) _corresponds to a widely spread out function, indicating involvement in describing long-range interactions or diffuse electrons (such as in anions or excited states).
- The largest exponent (5484.6716600000) corresponds to a very contracted function, useful for describing core electrons or regions very close to nuclei.
- Type -S- indicates these are s-type orbitals (spherical symmetry).
- Radial normalization = 1.000000 for both smallest and largest exponents ensures that the functions are properly normalized for accurate calculations.
138 Direct SCF iterations begin...
139 ===============================================================================================
140 Iteration Energy DeltaE Skip Error Conv
141 ===============================================================================================
142 1 -75.5246623667 -75.5246623667 0 0.71504778 SD
143 2 -76.0720337296 -0.5473713629 0 0.07265210 C-DIIS
144 3 -76.0771389941 -0.0051052645 0 0.01868587 C-DIIS
145 4 -76.0773577720 -0.0002187779 0 0.00961078 C-DIIS
146 5 -76.0774338910 -0.0000761190 0 0.00102724 C-DIIS
147 6 -76.0774351060 -0.0000012150 0 0.00014020 C-DIIS
148 7 -76.0774351212 -0.0000000153 0 0.00000853 C-DIIS
149 8 -76.0774351214 -0.0000000002 0 0.00000053 C-DIIS
150 ----------------------------------------------------------------
151 SCF convergence achieved ....
152
153 Final ROHF energy is -76.0774351214 after 8 iterations
154
155
156 DFT: XC energy = -4.7785703259
157 DFT: total electron density = 10.0000405899
158 DFT: number of electrons = 10
159
In this portion you can see all iteration in SCF procedure, starting from the initial guess of the electron density, moving through successive refinements. In the last column, Conv located which means the convergence method employed, with "SD" standing for steepest descent in the first iteration and "C-DIIS" denoting the Conjugate-Direction Direct Inversion in the Iterative Subspace method used in subsequent iterations to accelerate convergence.
The log file demonstrates the SCF process converging to a final Restricted Open-Shell Hartree-Fock (ROHF) energy of -76.0774351214 Hartrees after 8 iterations, which indicates efficient convergence to a stable electronic structure.
161 ===============================
162 Molecular Orbitals and Energies
163 ===============================
164
165 -------------- Alpha Orbitals -------------
166
167 1 2 3 4 5
168 -19.8714502618 -1.2828277384 -0.7345645566 -0.6116633038 -0.3978704556
169 1 O 1 S -0.9935640348 -0.2143498030 -0.0000000000 -0.0670599080 0.0000000000
170 2 O 1 S -0.0241337111 0.5118822273 0.0000000000 0.1523508053 0.0000000000
171 3 O 1 S -0.0078530668 0.4090814275 -0.0000000000 0.2684598925 -0.0000000000
172 4 O 1 X 0.0000000000 0.0000000000 -0.4049851169 0.0000000000 -0.5037391549
173 5 O 1 Y 0.0000000000 -0.0000000000 0.4049851169 -0.0000000000 -0.5037391549
174 6 O 1 Z 0.0005672855 -0.1046688476 0.0000000000 0.6185575504 0.0000000000
175 7 O 1 X 0.0000000000 -0.0000000000 -0.2168488816 -0.0000000000 -0.3038456887
176 8 O 1 Y -0.0000000000 0.0000000000 0.2168488816 0.0000000000 -0.3038456887
177 9 O 1 Z 0.0000063379 -0.0384589565 0.0000000000 0.3779120969 0.0000000000
178 10 O 1 XX 0.0064364634 0.0137490170 0.0000000000 0.0044948753 0.0000000000
179 11 O 1 YY 0.0064364634 0.0137490170 -0.0000000000 0.0044948753 0.0000000000
180 12 O 1 ZZ 0.0063101032 0.0178214626 -0.0000000000 -0.0380910372 0.0000000000
181 13 O 1 XY 0.0000736824 -0.0150304631 -0.0000000000 0.0054556305 0.0000000000
182 14 O 1 XZ -0.0000000000 0.0000000000 0.0303578651 0.0000000000 0.0200045485
183 15 O 1 YZ 0.0000000000 0.0000000000 -0.0303578651 -0.0000000000 0.0200045485
184 16 H 2 S -0.0003707529 0.1242508893 0.2091458235 -0.1269584314 0.0000000000
185 17 H 2 S 0.0006266880 0.0042916930 0.0629976771 -0.0492357228 0.0000000000
186 18 H 3 S -0.0003707529 0.1242508893 -0.2091458235 -0.1269584314 -0.0000000000
187 19 H 3 S 0.0006266880 0.0042916930 -0.0629976771 -0.0492357228 -0.0000000000
188
189 6 7 8 9 10
190 0.0083874571 0.1541069425 0.8006793543 0.8414713141 0.8537231289
191 1 O 1 S -0.1029907943 -0.0000000000 -0.0000000000 -0.0186340579 -0.0000000000
192 2 O 1 S 0.1906259841 -0.0000000000 -0.0000000000 -0.5740948076 0.0000000000
193 3 O 1 S 1.1789875323 0.0000000000 0.0000000000 1.0545620554 -0.0000000000
194 4 O 1 X -0.0000000000 0.2738842308 0.0553669892 -0.0000000000 -0.6436234885
195 5 O 1 Y 0.0000000000 -0.2738842308 -0.0553669892 0.0000000000 -0.6436234885
196 6 O 1 Z -0.2582971515 0.0000000000 -0.0000000000 -0.8497072611 0.0000000000
197 7 O 1 X -0.0000000000 0.5048825961 0.4253215528 0.0000000000 0.7584784230
198 8 O 1 Y 0.0000000000 -0.5048825961 -0.4253215528 0.0000000000 0.7584784230
199 9 O 1 Z -0.3996807281 -0.0000000000 0.0000000000 0.8883156083 -0.0000000000
200 10 O 1 XX -0.0366513706 -0.0000000000 -0.0000000000 -0.2011959477 0.0000000000
201 11 O 1 YY -0.0366513706 -0.0000000000 -0.0000000000 -0.2011959477 0.0000000000
202 12 O 1 ZZ -0.0233509846 -0.0000000000 -0.0000000000 -0.2209316956 0.0000000000
203 13 O 1 XY 0.0071834849 -0.0000000000 0.0000000000 0.0382934313 -0.0000000000
204 14 O 1 XZ -0.0000000000 -0.0027778769 0.1598505339 -0.0000000000 -0.0108873705
205 15 O 1 YZ 0.0000000000 0.0027778769 -0.1598505339 0.0000000000 -0.0108873705
206 16 H 2 S -0.1275908455 0.1207176158 0.8222665170 -0.0929535765 0.0000000000
207 17 H 2 S -0.9405310557 1.2994242549 -0.5240494184 0.0495265752 -0.0000000000
208 18 H 3 S -0.1275908455 -0.1207176158 -0.8222665170 -0.0929535765 -0.0000000000
209 19 H 3 S -0.9405310557 -1.2994242549 0.5240494184 0.0495265752 0.0000000000
210
211 11 12 13 14 15
212 0.9103753817 1.0650992556 1.1773111704 1.6888444348 1.6941919033
213 1 O 1 S 0.0303840680 0.0000000000 0.0830277780 0.0000000000 -0.0038836978
214 2 O 1 S -0.6005286944 0.0000000000 1.4640401261 0.0000000000 -0.0674922437
215 3 O 1 S 0.9667174978 -0.0000000000 -3.6715354161 -0.0000000000 0.1797216142
216 4 O 1 X -0.0000000000 0.6967058828 -0.0000000000 -0.0000000000 0.0000000000
217 5 O 1 Y 0.0000000000 -0.6967058828 0.0000000000 0.0000000000 0.0000000000
218 6 O 1 Z 0.1687233463 -0.0000000000 -0.4046321261 -0.0000000000 0.0045967349
219 7 O 1 X 0.0000000000 -1.1558739414 0.0000000000 -0.0000000000 0.0000000000
220 8 O 1 Y -0.0000000000 1.1558739414 -0.0000000000 -0.0000000000 -0.0000000000
221 9 O 1 Z 0.2261532857 0.0000000000 1.1062450596 0.0000000000 -0.1097638449
222 10 O 1 XX -0.1294197274 0.0000000000 0.4407297763 0.8660254038 0.4856211076
223 11 O 1 YY -0.1294197274 0.0000000000 0.4407297763 -0.8660254038 0.4856211076
224 12 O 1 ZZ -0.1560766725 0.0000000000 0.3902217213 0.0000000000 -1.0030878467
225 13 O 1 XY -0.2313178289 -0.0000000000 -0.2389871007 0.0000000000 -0.0946302936
226 14 O 1 XZ 0.0000000000 0.0135257750 0.0000000000 -0.0000000000 -0.0000000000
227 15 O 1 YZ -0.0000000000 -0.0135257750 -0.0000000000 -0.0000000000 0.0000000000
228 16 H 2 S 0.8310636919 0.0945570296 0.3002156904 0.0000000000 -0.0671946126
229 17 H 2 S -0.6732014045 -1.0452388253 0.8503588997 0.0000000000 -0.0298090510
230 18 H 3 S 0.8310636919 -0.0945570296 0.3002156904 0.0000000000 -0.0671946126
231 19 H 3 S -0.6732014045 1.0452388253 0.8503588997 0.0000000000 -0.0298090510
232
233 16 17 18 19
234 1.7258549631 2.2901604403 2.6205849317 3.5650833583
235 1 O 1 S -0.0000000000 -0.0645575391 -0.0000000000 -0.4688125339
236 2 O 1 S -0.0000000000 -0.5122494716 -0.0000000000 0.2649365007
237 3 O 1 S 0.0000000000 1.7076521135 0.0000000000 3.7551015718
238 4 O 1 X 0.0043434749 0.0000000000 0.0052604023 0.0000000000
239 5 O 1 Y 0.0043434749 -0.0000000000 -0.0052604023 -0.0000000000
240 6 O 1 Z 0.0000000000 0.0432254270 0.0000000000 0.1195588158
241 7 O 1 X 0.0202848763 0.0000000000 -0.6507637016 -0.0000000000
242 8 O 1 Y 0.0202848763 -0.0000000000 0.6507637016 0.0000000000
243 9 O 1 Z -0.0000000000 -0.7837676709 -0.0000000000 -0.3230954766
244 10 O 1 XX 0.0000000000 -0.1906681056 -0.0000000000 -1.5618580470
245 11 O 1 YY -0.0000000000 -0.1906681056 -0.0000000000 -1.5618580470
246 12 O 1 ZZ 0.0000000000 -0.0069390980 -0.0000000000 -1.5688839929
247 13 O 1 XY 0.0000000000 -1.0907621136 -0.0000000000 -0.0086502363
248 14 O 1 XZ 0.7067398978 -0.0000000000 0.9133438224 0.0000000000
249 15 O 1 YZ 0.7067398978 0.0000000000 -0.9133438224 -0.0000000000
250 16 H 2 S 0.0000000000 -0.8842955309 -0.9913481425 0.1427923891
251 17 H 2 S -0.0000000000 -0.1669599215 0.0288478688 -0.5793130453
252 18 H 3 S 0.0000000000 -0.8842955309 0.9913481425 0.1427923891
253 19 H 3 S -0.0000000000 -0.1669599215 -0.0288478688 -0.5793130453
This portion of log file demonstrates the Molecular Orbitals and their Energies.
In the calculation we used ROHF method, which is a hybrid approach that allows for both closed and open-shell systems. It maintains paired electrons in the same spatial orbitals (like RHF) while allowing unpaired electrons to have different spatial wavefunctions for α and β spins.
- Molecular Orbitals and Energies: The list begins with the energy levels of the first five molecular orbitals (denoted by numbers 1 through 5). These energy values are given in atomic units (Hartrees), with the more negative values indicating lower energy (more stable) orbitals. For example, the first orbital has a significantly lower energy (-19.8714502618 Hartrees) compared to the others, suggesting it is the most stable and likely represents a core orbital associated with the oxygen atom in the system.
- Contribution of Atomic Orbitals: Following the orbital energies, the table breaks down the composition of each molecular orbital in terms of atomic orbitals from the constituent atoms, labeled with their atomic number, type of orbital (S, P, etc.), and their respective contributions to each MO. For instance, "1 O 1 S" denotes the contribution of the 1s orbital of the first (oxygen) atom to the molecular orbitals. The coefficients (e.g., -0.9935640348 for the first MO) indicate the weight of each atomic orbital in the composition of the MO. A zero coefficient means that the atomic orbital does not contribute to the molecular orbital.
- Symmetry and Contributions: The presence of zeroes for certain orbitals at specific MOs hints at symmetry considerations within the molecule that affect orbital overlap and contributions. For example, orbitals labeled "X", "Y", and "Z" show the directional properties of p orbitals and their contributions to MOs, which are crucial for understanding the spatial distribution and chemical bonding characteristics of electrons in the molecule.
The next section of the log file is Energy components, Please notice this section does not contain gradient and response calculation information.
255 =================
256 Energy components
257 =================
258
259 Wavefunction normalization = 1.0000000000
260
261 One electron energy = -121.5660379888
262 Two electron energy = 36.1999095591
263 Nuclear repulsion energy = 9.2886933083
264 ------------------
265 TOTAL energy = -76.0774351214
266
267 Electron-electron potential energy = 36.1999095591
268 Nucleus-electron potential energy = -197.7919011895
269 Nucleus-nucleus potential energy = 9.2886933083
270 ------------------
271 TOTAL potential energy = -152.3032983221
272 TOTAL kinetic energy = 76.2258632007
273 Virial ratio (V/T) = 1.9980527859
274
275 Step CPU time in seconds = 34.9 wall time in seconds = 0.5
276 Total CPU time in seconds = 36.6 wall time in seconds = 0.5
277
- Wavefunction Normalization = 1.0000000000: This indicates that the calculated wavefunction is correctly normalized. Normalization ensures that the total probability density of finding electrons within the molecular system sums up to one, a fundamental requirement for valid quantum mechanical solutions.
- One Electron Energy = -121.5660379888 Hartrees: This component represents the sum of the energies associated with each electron moving in the average field created by all other electrons and nuclei. It includes the kinetic energy of the electrons and their potential energy due to interactions with nuclei.
- Two Electron Energy = 36.1999095591 Hartrees: This term accounts for the repulsion energy between pairs of electrons due to their charge interactions. It highlights electron-electron correlation effects not captured by the one-electron energy.
- Nuclear Repulsion Energy = 9.2886933083 Hartrees: This energy component is the electrostatic potential energy due to repulsions between the positively charged nuclei in the molecule. It's independent of the electronic state and depends only on the positions of the nuclei.
- TOTAL Energy = -76.0774351214 Hartrees: The sum of the one-electron, two-electron, and nuclear repulsion energies, representing the total energy of the molecular system.
- Potential and Kinetic Energy Components: Additional details provide insights into the distribution of potential and kinetic energies within the system, including electron-electron, nucleus-electron, and nucleus-nucleus potential energies. The total potential energy sums to -152.3032983221 Hartrees, while the total kinetic energy of the electrons is reported as 76.2258632007 Hartrees.
- Virial Ratio (V/T) = 1.9980527859: The virial theorem relates the average total kinetic energy (T) of a system to its total potential energy (V), with the ratio providing insights into the system's dynamical properties. A ratio close to 2 indicates that the system is in a stable quantum mechanical state under the influence of Coulomb forces.
This segment of the log file introduces the setup and execution of Time-Dependent Density Functional Theory (TDDFT) steps.
278 ==============================================
279 PyOQP: TDDFT steps
280 ==============================================
281
282 PyOQP method: tdhf
283 PyOQP functional: bhhlyp
284 PyOQP td type: mrsf
285 PyOQP td maxit: 50
286 PyOQP td multiplicity: 1
287 PyOQP td convergence: 1e-06
288 PyOQP td number of states: 3
289 PyOQP td z-vector of convergence: 1e-06
290 PyOQP td dimension of Davidson: 50
291
292
293 ++++++++++++++++++++++++++++++++++++++++
294 MODULE: MRSF_TDHF_Energy
295 Computing Energy of MRSF-TDDFT
296 ++++++++++++++++++++++++++++++++++++++++
This part of the log file documents the use of the Davidson algorithm in calculating the energies of singlet response states as part of a Time-Dependent Density Functional Theory (TDDFT) calculation. The Davidson algorithm is a numerical method designed to find a few of the lowest eigenvalues (and corresponding eigenvectors) of large matrices.
298 ==============================================
299 Davidson algorithm for SINGLET response states
300 ==============================================
301
302 Davidson iteration # 1
303 State 1 E = -7.371697 eV err. = 0.015876
304 State 2 E = 1.330138 eV err. = 0.005446
305 State 3 E = 2.883993 eV err. = 0.002930
306 Max error = 1.588E-02 / 1.000E-06
307
308 Davidson iteration # 2
309 State 1 E = -7.714415 eV err. = 0.000022
310 State 2 E = 1.233681 eV err. = 0.000037
311 State 3 E = 2.818417 eV err. = 0.000015
312 Max error = 3.743E-05 / 1.000E-06
313
314 Davidson iteration # 3
315 State 1 E = -7.714759 eV err. = 0.000000
316 State 2 E = 1.232645 eV err. = 0.000001
317 State 3 E = 2.818164 eV err. = 0.000000
318 Max error = 9.441E-07 / 1.000E-06
319
320 MRSF-TD-DFT energies converged in 3 iterations
321
Davidson Iterations
The log shows three iterations of the Davidson algorithm, with each iteration refining the energies (E) of the first three excited states of the system, measured in electron volts (eV), and their associated errors.
- Iteration # 1: Initial estimates of the energies for the three states are provided, with the largest error in the estimates reported as 1.588e−2. This step sets the baseline for subsequent refinements.
- Iteration # 2: The energy values are updated, and the errors are significantly reduced, showing the algorithm's effectiveness in quickly honing in on accurate values. The maximum error decreases dramatically to 3.743e-5.
- Iteration # 3: By the third iteration, the energies of the states have further converged to highly precise values, with the maximum error now below the convergence threshold (1e-6), indicating successful convergence of the calculations.
The energies of the excited states after convergence are as follows:
- State 1: -7.714759 eV
- State 2: 1.232645 eV
- State 3: 2.818164 eV
This section of the log file provides detailed information on spin-adapted spin-flip excitations.
323 ===================================
324 Spin-adapted spin-flip excitations
325 ===================================
326
327 State # 1 Energy = -7.714758 eV
328 <S^2> = 0.0000
329 DRF Coeff OCC VIR
330 --- -------- ------ ------
331 4 -0.063155 4 -> 5
332 6 0.992805 6 -> 5
333 35 -0.098780 6 -> 10
334
335 State # 2 Energy = 1.232645 eV
336 <S^2> = 0.0000
337 DRF Coeff OCC VIR
338 --- -------- ------ ------
339 5 -0.998471 5 -> 5
340
341 State # 3 Energy = 2.818164 eV
342 <S^2> = 0.0000
343 DRF Coeff OCC VIR
344 --- -------- ------ ------
345 17 -0.998701 6 -> 7
346
- State # 1, # 2, and # 3: These entries detail the energies and properties of the first three excited states resulting from spin-flip transitions. Each state's energy is provided in electron volts (eV), and the expectation value of the squared spin operator, <S^2>, is given, indicating the spin purity of the state. In this case, all states have <S^2> = 0.0000, suggesting they are pure singlet states.
- DRF (Dominant Response Functions), Coefficients, OCC (Occupied), and VIR (Virtual): This part lists the most significant contributions to each excited state in terms of single-electron transitions between occupied (OCC) and virtual (VIR) molecular orbitals. The coefficients indicate the magnitude and sign of each contribution. For example, for State # 1, a significant transition is observed from orbital 6 to orbital 5 with a coefficient of 0.992805, denoting a major contributor to this excitation.
The next section of the log file is Summary table which contains the iformation response theo
347 Summary table
348
349 State Energy Excitation Excitation(eV) <S^2> Transition dipole moment, A.U. Oscillator
350 Hartree eV rel. GS X Y Z Abs. strength
351 1 -76.3609472818 -7.714758 0.000000 0.000 0.0000 0.0000 0.0000 0.0000 0.0000
352 0 -76.0774351214 0.000000 7.714758 (ROHF/UHF Reference state)
353 2 -76.0321362505 1.232645 8.947403 0.000 -0.1790 -0.1790 -0.0000 0.2532 0.0140
354 3 -75.9738695106 2.818164 10.532922 0.000 0.0000 0.0000 0.0000 0.0000 0.0000
355
356 Step CPU time in seconds = 14.0 wall time in seconds = 0.2
357 Total CPU time in seconds = 50.6 wall time in seconds = 0.7
- State 0 is identified as the ROHF/UHF (Restricted Open-Shell Hartree-Fock/Unrestricted Hartree-Fock) reference state, with an energy of -76.0774351214 Hartrees. This is our reference state.
- State 1 shows an excitation energy of -7.714758 eV relative to the ground state (This is our S0 state), indicating a lower energy state than the reference, with a <S^2> value of 0.000, suggesting it maintains a singlet character. Its transition dipole moment in all directions (X, Y, Z) is 0.0000 A.U., and it has an oscillator strength of 0.0000, indicating it may not be optically active.
- State 2 (S1 state) has an excitation energy of 1.232645 eV with a relative energy difference from the ground state of 8.947403 eV. The transition dipole moments are -0.1790 A.U. in the X and Y directions and -0.0000 A.U. in the Z direction, with an absolute magnitude of 0.2532 A.U. Its oscillator strength of 0.0140 suggests a weak but non-zero probability of transition from the ground state, indicating potential optical activity.
- State 3 (S2 state) is excited to 2.818164 eV above the reference state, with a total relative excitation energy of 10.532922 eV. Similar to State 1, its transition dipole moments are 0.0000 in all directions, and it has an oscillator strength of 0.0000, suggesting no optical activity.
This section of the log file provides information about the dispersion correction settings. Dispersion corrections are important for accurately modeling long-range van der Waals (vdW) interactions, which are often poorly represented in conventional Density Functional Theory (DFT) calculations.
359 ==============================================
360 PyOQP: Dispersion Correction
361 ==============================================
362
363 PyOQP dftd correction: False
364 PyOQP dftd method: dftd4
365 PyOQP dftd functional: bhhlyp
- PyOQP dftd correction: The setting False indicates that dispersion corrections were not applied in this particular set of calculations. Dispersion corrections are often necessary for accurately predicting intermolecular interactions, molecular geometries, and binding energies, especially in systems where van der Waals forces play a significant role.
- PyOQP dftd method: Despite dispersion corrections being disabled, the method specified for such corrections is dftd4. The DFT-D4 method is a recent and advanced scheme for computing dispersion corrections, known for its accuracy and applicability to a wide range of molecules and materials. It calculates dispersion energies based on a set of atom-pairwise terms adjusted for each element, considering their chemical environment.
- PyOQP dftd functional: You can find the full explanation for this part in the input files wiki page.
The next part of the log file indicates Final energy, first electronic energies which we saw at the previous section and the the energy of the same states but with considering the Dispersion Correction, as we menstioned in the last section:
363 PyOQP dftd correction: False
so there will be no difference between the "PyOQP electronic energies" and "PyOQP dispersion corrected energies".
368 ==============================================
369 PyOQP: Final Energy
370 ==============================================
371 PyOQP electronic energies
372 PyOQP state 0 -76.07743512
373 PyOQP state 1 -76.36094728
374 PyOQP state 2 -76.03213625
375 PyOQP state 3 -75.97386951
376
377 PyOQP dftd correction 0.00000000
378
379 PyOQP dispersion corrected energies
380 PyOQP state 0 -76.07743512
381 PyOQP state 1 -76.36094728
382 PyOQP state 2 -76.03213625
383 PyOQP state 3 -75.97386951
Electric Charge
- C_o: The total electric charge of the molecule is given in atomic units (a.u.), here reported as +0.00000, indicating the molecule is overall neutral. This is a fundamental property that influences how the molecule interacts electrostatically with its surroundings.
Electric Dipole Moment
- D_o: The electric dipole moment, measured in Debye, is a vector quantity that describes the separation of positive and negative charges within the molecule. The analysis reports the dipole moment components along the X, Y, and Z axes, with a significant value along the Z-axis (0.51758202 Debye) and a norm of the same magnitude, indicating an asymmetrical charge distribution primarily along the Z-axis. This property affects the molecule's interaction with external electric fields and is related to molecular polarity.
Electric Quadrupole Moment
- Q_X, Q_Y, Q_Z: The electric quadrupole moments, provided in Buckingham units, quantify the distribution of charge that creates a quadrupole, or a pair of dipoles. These values give a more nuanced view of the molecule's electrostatic field than the dipole moment alone, describing how charge distributions vary in space, which influences intermolecular interactions and spectroscopic properties.
Electric Octupole Moment
- O_xxx, O_xxy, ...: The electric octupole moments, measured in Buckingham*Angstrom units, offer an even more detailed representation of the molecule's electrostatic potential, accounting for complex distributions of charge that extend beyond those described by the dipole and quadrupole moments. These higher-order moments can be significant for large molecules or those with complex shapes.
The Mulliken population analysis section of the log file provides detailed insights into the electron distribution among atomic orbitals (AOs):
422 ============================
423 Mulliken population analysis
424 ============================
425
426 Gross AO population (Mulliken)
427
428 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
429
430 # A N L Population
431 ----------------------------------
432 1 O 1 S 1.994243
433 2 O 1 S 1.009685
434 3 O 1 S 0.644704
435 4 O 1 X 0.811150
436 5 O 1 Y 0.811150
437 6 O 1 Z 1.165173
438 7 O 1 X 0.425756
439 8 O 1 Y 0.425756
440 9 O 1 Z 0.580985
441 10 O 1 XX 0.019243
442 11 O 1 YY 0.019243
443 12 O 1 ZZ 0.015065
444 13 O 1 XY 0.003731
445 14 O 1 XZ 0.008436
446 15 O 1 YZ 0.008436
447 16 H 2 S 0.439508
448 17 H 2 S 0.589113
449 18 H 3 S 0.439508
450 19 H 3 S 0.589113
451 ==================================
Orbital Entries:
- The first column (#) lists the orbital indices.
- The second column (A) identifies the atom type (O for oxygen, H for hydrogen).
- The third column (N) indicates the atom number within the molecule.
- The fourth column (L) specifies the type of orbital (S for s-orbital, X, Y, Z for p-orbitals, XX, YY, ZZ for d-orbitals, etc.).
- The fifth column (Population) provides the Mulliken population or the estimated number of electrons in each orbital.
Interpretation
- Oxygen Atom: The Mulliken populations for the oxygen atom's orbitals vary, with the 1s orbital (entries 1-3) showing a significant population, indicative of its core electrons. The p-orbitals (entries 4-9) and d-orbitals (entries 10-15) have lower populations, reflecting the valence electron distribution and hybridization state of oxygen in the molecule. - **Hydrogen Atoms**: The populations for the 1s orbitals of the hydrogen atoms (entries 16-19) are less than 1, suggesting partial sharing of these electrons with oxygen, consistent with covalent bonding in water.The last section of this log file demonstrates atomic partial charges derived from the Mulliken population analysis offers insight into the distribution of electronic charge across different atoms within the molecule.
453 Atomic partial charges (Mulliken)
454
455 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
456
457 # Name Charge
458 ------------------------------
459 1 O 0.057243
460 2 H -0.028622
461 3 H -0.028622
462 ==============================
- Oxygen (O) has a partial charge of +0.057243, suggesting it holds a slight positive charge relative to its standard state. This positive value indicates that oxygen, in the context of this molecule, is slightly electron-deficient.
- Hydrogen (H) atoms each have a partial charge of -0.028622, implying they are slightly electron-rich compared to their neutral state. This negative value reflects a small accumulation of electron density on the hydrogen atoms.