The study of photochemical reaction dynamics requires accurate as well as computationally efficient electronic structure methods for the ground and excited states. While time-dependent density functional theory (TDDFT) is not able to capture static correlation, complete active space self-consistent field methods neglect much of the dynamic correlation. Hence, inexpensive methods that encompass both static and dynamic electron correlation effects are of high interest. Here, we revisit hole–hole Tamm–Dancoff approximated (hh-TDA) density functional theory for this purpose. The hh-TDA method is the hole–hole counterpart to the more established particle–particle TDA (pp-TDA) method, both of which are derived from the particle–particle random phase approximation (pp-RPA). In hh-TDA, the N-electron electronic states are obtained through double annihilations starting from a doubly anionic (N+2 electron) reference state. In this way, hh-TDA treats ground and excited states on equal footing, thus allowing for conical intersections to be correctly described. The treatment of dynamic correlation is introduced through the use of commonly employed density functional approximations to the exchange-correlation potential. We show that hh-TDA is a promising candidate to efficiently treat the photochemistry of organic and biochemical systems that involve several low-lying excited states—particularly those with both low-lying ππ* and nπ* states where inclusion of dynamic correlation is essential to describe the relative energetics. In contrast to the existing literature on pp-TDA and pp-RPA, we employ a functional-dependent choice for the response kernel in pp- and hh-TDA, which closely resembles the response kernels occurring in linear response and collinear spin-flip TDDFT.

1.
A.
Dreuw
and
M.
Head-Gordon
, “
Single-reference ab initio methods for the calculation of excited states of large molecules
,”
Chem. Rev.
105
,
4009
4037
(
2005
).
2.
B. G.
Levine
,
C.
Ko
,
J.
Quenneville
, and
T. J.
Martínez
, “
Conical intersections and double excitations in time-dependent density functional theory
,”
Mol. Phys.
104
,
1039
1051
(
2006
).
3.
B. O.
Roos
, “
The complete active space SCF method in a fock-matrix-based super-CI formulation
,”
Int. J. Quantum Chem.
18
,
175
189
(
1980
).
4.
B. O.
Roos
, “
Theoretical studies of electronically excited states of molecular systems using multiconfigurational perturbation theory
,”
Acc. Chem. Res.
32
,
137
144
(
1999
).
5.
H. J.
Werner
and
P. J.
Knowles
, “
An efficient internally contracted multiconfiguration reference configuration-interaction method
,”
J. Chem. Phys.
89
,
5803
5814
(
1988
).
6.
J. D.
Coe
,
B. G.
Levine
, and
T. J.
Martínez
, “
Ab initio molecular dynamics of excited state intramolecular proton transfer using multireference perturbation theory
,”
J. Phys. Chem. A
111
,
11302
11310
(
2007
).
7.
H.
Tao
,
B. G.
Levine
, and
T. J.
Martínez
, “
Ab initio multiple spawning dynamics using multi-state second-order perturbation theory
,”
J. Phys. Chem. A
113
,
13656
13662
(
2009
).
8.
H.
Tao
,
T. K.
Allison
,
T. W.
Wright
,
A. M.
Stooke
,
C.
Khurmi
,
J.
van Tilborg
,
Y.
Liu
,
R. W.
Falcone
,
A.
Belkacem
, and
T. J.
Martinez
, “
Ultrafast internal conversion in ethylene. I. The excited state lifetime
,”
J. Chem. Phys.
134
,
244306
(
2011
).
9.
T.
Mori
,
W. J.
Glover
,
M. S.
Schuurman
, and
T. J.
Martinez
, “
Role of Rydberg states in the photochemical dynamics of ethylene
,”
J. Phys. Chem. A
116
,
2808
2818
(
2012
).
10.
L.
Liu
,
J.
Liu
, and
T. J.
Martinez
, “
Dynamical correlation effects on photoisomerization: Ab initio multiple spawning dynamics with MS-CASPT2 for a model trans-protonated schiff base
,”
J. Phys. Chem. B
120
,
1940
1949
(
2016
).
11.
J. W.
Park
and
T.
Shiozaki
, “
On-the-fly CASPT2 surface-hopping dynamics
,”
J. Chem. Theory Comput.
13
,
3676
3683
(
2017
).
12.
W. J.
Glover
,
T.
Mori
,
M. S.
Schuurman
,
A. E.
Boguslavskiy
,
O.
Schalk
,
A.
Stolow
, and
T. J.
Martínez
, “
Excited state non-adiabatic dynamics of the smallest polyene, trans 1,3-butadiene. II. Ab initio multiple spawning simulations
,”
J. Chem. Phys.
148
,
164303
(
2018
).
13.
J. W.
Snyder
,
R. M.
Parrish
, and
T. J.
Martínez
, “
α-CASSCF: An efficient, empirical correction for SA-CASSCF to closely approximate MS-CASPT2 potential energy surfaces
,”
J. Phys. Chem. Lett.
8
,
2432
2437
(
2017
).
14.
A.
Koslowski
,
M. E.
Beck
, and
W.
Thiel
, “
Implementation of a general multireference configuration interaction procedure with analytic gradients in a semiempirical context using the graphical unitary group approach
,”
J. Comput. Chem.
24
,
714
726
(
2003
).
15.
A.
Toniolo
,
A. L.
Thompson
, and
T. J.
Martínez
, “
Excited state direct dynamics of benzene with reparameterized multi-reference semiempirical configuration interaction methods
,”
Chem. Phys.
304
,
133
145
(
2004
).
16.
A.
Toniolo
,
G.
Granucci
,
S.
Inglese
, and
M.
Persico
, “
Theoretical study of the photodissociation dynamics of ClOOCl
,”
Phys. Chem. Chem. Phys.
3
,
4266
4279
(
2001
).
17.
K.
Sastry
,
D. D.
Johnson
,
A. L.
Thompson
,
D. E.
Goldberg
,
T. J.
Martinez
,
J.
Leiding
, and
J.
Owens
, “
Optimization of semiempirical quantum chemistry methods via multiobjective genetic algorithms: Accurate photodynamics for larger molecules and longer time scales
,”
Mater. Manuf. Processes
22
,
553
561
(
2007
).
18.
S.
Ghosh
,
P.
Verma
,
C. J.
Cramer
,
L.
Gagliardi
, and
D. G.
Truhlar
, “
Combining wave function methods with density functional theory for excited states
,”
Chem. Rev.
118
,
7249
7292
(
2018
).
19.
S.
Pijeau
and
E. G.
Hohenstein
, “
Improved complete active space configuration interaction energies with a simple correction from density functional theory
,”
J. Chem. Theory Comput.
13
,
1130
1146
(
2017
).
20.
B.
Miehlich
,
H.
Stoll
, and
A.
Savin
, “
A correlation-energy density functional for multideterminantal wavefunctions
,”
Mol. Phys.
91
,
527
536
(
1997
).
21.
C.
Gutle
and
A.
Savin
, “
Orbital spaces and density-functional theory
,”
Phys. Rev. A
75
,
032519
(
2007
).
22.
L.
Gagliardi
,
D. G.
Truhlar
,
G.
Li Manni
,
R. K.
Carlson
,
C. E.
Hoyer
, and
J. W. L.
Bao
, “
Multiconfiguration pair-density functional theory: A new way to treat strongly correlated systems
,”
Acc. Chem. Res.
50
,
66
73
(
2017
).
23.
A. M.
Sand
,
C. E.
Hoyer
,
D. G.
Truhlar
, and
L.
Gagliardi
, “
State-interaction pair-density functional theory
,”
J. Chem. Phys.
149
,
024106
(
2018
).
24.
S. L.
Li
,
A. V.
Marenich
,
X.
Xu
, and
D. G.
Truhlar
, “
Configuration interaction-corrected Tamm–Dancoff approximation: A time-dependent density functional method with the correct dimensionality of conical intersections
,”
J. Phys. Chem. Lett.
5
,
322
328
(
2014
).
25.
H.-H.
Teh
and
J. E.
Subotnik
, “
The simplest possible approach for simulating S0–S1 conical intersections with DFT/TDDFT: Adding one doubly excited configuration
,”
J. Phys. Chem. Lett.
10
,
3426
3432
(
2019
).
26.
S.
Grimme
and
M.
Waletzke
, “
A combination of Kohn–Sham density functional theory and multi-reference configuration interaction methods
,”
J. Chem. Phys.
111
,
5645
5655
(
1999
).
27.
C. M.
Marian
,
A.
Heil
, and
M.
Kleinschmidt
, “
The DFT/MRCI method
,”
Wiley Interdiscip. Rev.: Comput. Mol. Sci.
9
,
e1394
(
2019
).
28.
Y.
Shu
,
K. A.
Parker
, and
D. G.
Truhlar
, “
Dual-functional Tamm–Dancoff approximation: A convenient density functional method that correctly describes S1/S0 conical intersections
,”
J. Phys. Chem. Lett.
8
,
2107
2112
(
2017
).
29.
A. I.
Krylov
,
Y.
Shao
, and
M.
Head-Gordon
, “
The spin–flip approach within time-dependent density functional theory: Theory and applications to diradicals
,”
J. Chem. Phys.
118
,
4807
4818
(
2003
).
30.
J. S.
Sears
,
C. D.
Sherrill
, and
A. I.
Krylov
, “
A spin-complete version of the spin-flip approach to bond breaking: What is the impact of obtaining spin eigenfunctions?
,”
J. Chem. Phys.
118
,
9084
9094
(
2003
).
31.
D.
Casanova
and
M.
Head-Gordon
, “
The spin-flip extended single excitation configuration interaction method
,”
J. Chem. Phys.
129
,
064104
(
2008
).
32.
X.
Zhang
and
J. M.
Herbert
, “
Spin-flip, tensor equation-of-motion configuration interaction with a density-functional correction: A spin-complete method for exploring excited-state potential energy surfaces
,”
J. Chem. Phys.
143
,
234107
(
2015
).
33.
M.
Filatov
, “
Spin-restricted ensemble-referenced Kohn–Sham method: Basic principles and application to strongly correlated ground and excited states of molecules
,”
Wiley Interdiscip. Rev.: Comput. Mol. Sci.
5
,
146
167
(
2015
).
34.
M.
Filatov
,
F.
Liu
, and
T. J.
Martínez
, “
Analytical derivatives of the individual state energies in ensemble density functional theory method. I. General formalism
,”
J. Chem. Phys.
147
,
034113
(
2017
).
35.
F.
Liu
,
M.
Filatov
, and
T. J.
Martínez
, “
Analytical derivatives of the individual state energies in ensemble density functional theory method: II. Implementation on graphical processing units (GPUs)
,” ChemRxiv (published online
2019
).
36.
D.
Peng
,
S. N.
Steinmann
,
H.
van Aggelen
, and
W.
Yang
, “
Equivalence of particle–particle random phase approximation correlation energy and ladder-coupled-cluster doubles
,”
J. Chem. Phys.
139
,
104112
(
2013
).
37.
H.
van Aggelen
,
Y.
Yang
, and
W.
Yang
, “
Exchange-correlation energy from pairing matrix fluctuation and the particle–particle random-phase approximation
,”
Phys. Rev. A
88
,
030501
(
2013
).
38.
H.
van Aggelen
,
Y.
Yang
, and
W.
Yang
, “
Exchange-correlation energy from pairing matrix fluctuation and the particle–particle random phase approximation
,”
J. Chem. Phys.
140
,
18A511
(
2014
).
39.
Y.
Yang
,
H.
van Aggelen
,
S. N.
Steinmann
,
D.
Peng
, and
W.
Yang
, “
Benchmark tests and spin adaptation for the particle–particle random phase approximation
,”
J. Chem. Phys.
139
,
174110
(
2013
).
40.
N.
Shenvi
,
H.
van Aggelen
,
Y.
Yang
, and
W.
Yang
, “
Tensor hypercontracted ppRPA: Reducing the cost of the particle-particle random phase approximation from O(r 6) to O(r 4)
,”
J. Chem. Phys.
141
,
024119
(
2014
).
41.
G. E.
Scuseria
,
T. M.
Henderson
, and
I. W.
Bulik
, “
Particle–particle and quasiparticle random phase approximations: Connections to coupled cluster theory
,”
J. Chem. Phys.
139
,
104113
(
2013
).
42.
G. E.
Scuseria
,
T. M.
Henderson
, and
D. C.
Sorensen
, “
The ground state correlation energy of the random phase approximation from a ring coupled cluster doubles approach
,”
J. Chem. Phys.
129
,
231101
(
2008
).
43.
R.
Al-Saadon
,
C.
Sutton
, and
W.
Yang
, “
Accurate treatment of charge-transfer excitations and thermally activated delayed fluorescence using the particle–particle random phase approximation
,”
J. Chem. Theory Comput.
14
,
3196
3204
(
2018
).
44.
Y.
Jin
,
Y.
Yang
,
D.
Zhang
,
D.
Peng
, and
W.
Yang
, “
Excitation energies from particle–particle random phase approximation with accurate optimized effective potentials
,”
J. Chem. Phys.
147
,
134105
(
2017
).
45.
Y.
Yang
,
D.
Peng
,
J.
Lu
, and
W.
Yang
, “
Excitation energies from particle–particle random phase approximation: Davidson algorithm and benchmark studies
,”
J. Chem. Phys.
141
,
124104
(
2014
).
46.
C.
Sutton
,
Y.
Yang
,
D.
Zhang
, and
W.
Yang
, “
Single, double electronic excitations and exciton effective conjugation lengths in π-conjugated systems
,”
J. Phys. Chem. Lett.
9
,
4029
4036
(
2018
).
47.
Y.
Yang
,
A.
Dominguez
,
D.
Zhang
,
V.
Lutsker
,
T. A.
Niehaus
,
T.
Frauenheim
, and
W.
Yang
, “
Charge transfer excitations from particle–particle random phase approximation—Opportunities and challenges arising from two-electron deficient systems
,”
J. Chem. Phys.
146
,
124104
(
2017
).
48.
Y.
Yang
,
D.
Peng
,
E. R.
Davidson
, and
W.
Yang
, “
Singlet–triplet energy gaps for diradicals from particle–particle random phase approximation
,”
J. Phys. Chem. A
119
,
4923
4932
(
2015
).
49.
Y.
Yang
,
H.
van Aggelen
, and
W.
Yang
, “
Double, Rydberg and charge transfer excitations from pairing matrix fluctuation and particle–particle random phase approximation
,”
J. Chem. Phys.
139
,
224105
(
2013
).
50.
D.
Zhang
,
D.
Peng
,
P.
Zhang
, and
W.
Yang
, “
Analytic gradients, geometry optimization and excited state potential energy surfaces from the particle–particle random phase approximation
,”
Phys. Chem. Chem. Phys.
17
,
1025
1038
(
2015
).
51.
B.
Pinter
,
R.
Al-Saadon
,
Z.
Chen
, and
W.
Yang
, “
Spin-state energetics of iron(II) porphyrin from the particle–particle random phase approximation
,”
Eur. Phys. J. B
91
,
270
(
2018
).
52.
Y.
Yang
,
E. R.
Davidson
, and
W.
Yang
, “
Nature of ground and electronic excited states of higher acenes
,”
Proc. Natl. Acad. Sci. U. S. A.
113
,
E5098
(
2016
).
53.
Y.
Yang
,
L.
Shen
,
D.
Zhang
, and
W.
Yang
, “
Conical intersections from particle–particle random phase and Tamm–Dancoff approximations
,”
J. Phys. Chem. Lett.
7
,
2407
2411
(
2016
).
54.
D.
Peng
,
H.
van Aggelen
,
Y.
Yang
, and
W.
Yang
, “
Linear-response time-dependent density-functional theory with pairing fields
,”
J. Chem. Phys.
140
,
18A522
(
2014
).
55.
L. N.
Oliveira
,
E. K. U.
Gross
, and
W.
Kohn
, “
Density-functional theory for superconductors
,”
Phys. Rev. Lett.
60
,
2430
2433
(
1988
).
56.
E. K. U.
Gross
and
S.
Kurth
, “
Density-functional theory of the superconducting state
,”
Int. J. Quantum Chem.
40
,
289
297
(
1991
).
57.
M.
Lüders
,
M. A. L.
Marques
,
N. N.
Lathiotakis
,
A.
Floris
,
G.
Profeta
,
L.
Fast
,
A.
Continenza
,
S.
Massidda
, and
E. K. U.
Gross
, “
Ab initio theory of superconductivity. I. Density functional formalism and approximate functionals
,”
Phys. Rev. B
72
,
024545
(
2005
).
58.
M. E.
Casida
,
Time-Dependent Density Functional Response Theory for Molecules in: Recent Advances in Density Functional Methods
, edited by
D. P.
Chong
(
World Scientific
,
Singapore
,
1995
), Vol. 1.
59.
A.
Köhn
and
A.
Tajti
, “
Can coupled-cluster theory treat conical intersections?
,”
J. Chem. Phys.
127
,
044105
(
2007
).
60.
E. F.
Kjønstad
,
R. H.
Myhre
,
T. J.
Martínez
, and
H.
Koch
, “
Crossing conditions in coupled cluster theory
,”
J. Chem. Phys.
147
,
164105
(
2017
).
61.
J. C.
Rienstra-Kiracofe
,
G. S.
Tschumper
,
H. F.
Schaefer
,
S.
Nandi
, and
G. B.
Ellison
, “
Atomic and molecular electron affinities: Photoelectron experiments and theoretical computations
,”
Chem. Rev.
102
,
231
282
(
2002
).
62.
J. P.
Perdew
,
W.
Yang
,
K.
Burke
,
Z.
Yang
,
E. K. U.
Gross
,
M.
Scheffler
,
G. E.
Scuseria
,
T. M.
Henderson
,
I. Y.
Zhang
,
A.
Ruzsinszky
,
H.
Peng
,
J.
Sun
,
E.
Trushin
, and
A.
Görling
, “
Understanding band gaps of solids in generalized Kohn–Sham theory
,”
Proc. Natl. Acad. Sci. U. S. A.
114
,
2801
(
2017
).
63.
E. J.
Baerends
,
O. V.
Gritsenko
, and
R.
van Meer
, “
The Kohn–Sham gap, the fundamental gap and the optical gap: The physical meaning of occupied and virtual Kohn–Sham orbital energies
,”
Phys. Chem. Chem. Phys.
15
,
16408
16425
(
2013
).
64.
I. S.
Ufimtsev
and
T. J.
Martínez
, “
Quantum chemistry on graphical processing units. 1. Strategies for two-electron integral evaluation
,”
J. Chem. Theory Comput.
4
,
222
231
(
2008
).
65.
I. S.
Ufimtsev
and
T. J.
Martinez
, “
Quantum chemistry on graphical processing units. 2. Direct self-consistent-field implementation
,”
J. Chem. Theory Comput.
5
,
1004
1015
(
2009
).
66.
A. D.
Becke
, “
Density-functional exchange-energy approximation with correct asymptotic behaviour
,”
Phys. Rev. A
38
,
3098
3100
(
1988
).
67.
C.
Lee
,
W.
Yang
, and
R. G.
Parr
, “
Development of the Colle–Salvetti correlation-energy formula into a functional of the electron density
,”
Phys. Rev. B
37
,
785
789
(
1988
).
68.
A. D.
Becke
, “
Density-functional thermochemistry. III. The role of exact exchange
,”
J. Chem. Phys.
98
,
5648
5652
(
1993
).
69.
P. J.
Stephens
,
F. J.
Devlin
,
C. F.
Chabalowski
, and
M. J.
Frisch
, “
Ab initio calculation of vibrational absorption and circular Dichroism spectra using density functional force fields
,”
J. Phys. Chem.
98
,
11623
11627
(
1994
).
70.
J. P.
Perdew
,
K.
Burke
, and
M.
Ernzerhof
, “
Generalized gradient approximation made simple
,”
Phys. Rev. Lett.
77
,
3865
3868
(
1996
).
71.
C.
Adamo
and
V.
Barone
, “
Toward reliable density functional methods without adjustable parameters: The PBE0 model
,”
J. Chem. Phys.
110
,
6158
6170
(
1999
).
72.
A. D.
Becke
, “
A new mixing of Hartree–Fock and local density-functional theories
,”
J. Chem. Phys.
98
,
1372
1377
(
1993
).
73.
T.
Yanai
,
D. P.
Tew
, and
N. C.
Handy
, “
A new hybrid exchange–correlation functional using the Coulomb–attenuating method (CAM-B3LYP)
,”
Chem. Phys. Lett.
393
,
51
57
(
2004
).
74.
M. A.
Rohrdanz
,
K. M.
Martins
, and
J. M.
Herbert
, “
A long-range-corrected density functional that performs well for both ground-state properties and time-dependent density functional theory excitation energies, including charge-transfer excited states
,”
J. Chem. Phys.
130
,
054112
(
2009
).
75.
A. D.
Becke
, “
Density-functional thermochemistry. V. Systematic optimization of exchange-correlation functionals
,”
J. Chem. Phys.
107
,
8554
8560
(
1997
).
76.
J.-D.
Chai
and
M.
Head-Gordon
, “
Systematic optimization of long-range corrected hybrid density functionals
,”
J. Chem. Phys.
128
,
084106
(
2008
).
77.
Y.-S.
Lin
,
G.-D.
Li
,
S.-P.
Mao
, and
J.-D.
Chai
, “
Long-range corrected hybrid density functionals with improved dispersion corrections
,”
J. Chem. Theory Comput.
9
,
263
272
(
2013
).
78.
A.
Schäfer
,
H.
Horn
, and
R.
Ahlrichs
, “
Fully optimized contracted Gaussian basis sets for atoms Li to Kr
,”
J. Chem. Phys.
97
,
2571
2577
(
1992
).
79.
F.
Weigend
and
R.
Ahlrichs
, “
Balanced basis sets of split valence, triple zeta valence and quadruple zeta valence quality for H to Rn: Design and assessment of accuracy
,”
Phys. Chem. Chem. Phys.
7
,
3297
3305
(
2005
).
80.
A.
Schäfer
,
C.
Huber
, and
R.
Ahlrichs
, “
Fully optimized contracted Gaussian basis sets of triple zeta valence quality for atoms Li to Kr
,”
J. Chem. Phys.
100
,
5829
5835
(
1994
).
81.
M.
Schreiber
,
M. R.
Silva-Junior
,
S. P. A.
Sauer
, and
W.
Thiel
, “
Benchmarks for electronically excited states: CASPT2, CC2, CCSD, and CC3
,”
J. Chem. Phys.
128
,
134110
(
2008
).
82.
Y.
Shao
,
Z.
Gan
,
E.
Epifanovsky
,
A. T. B.
Gilbert
,
M.
Wormit
,
J.
Kussmann
,
A. W.
Lange
,
A.
Behn
,
J.
Deng
,
X.
Feng
,
D.
Ghosh
,
M.
Goldey
,
P. R.
Horn
,
L. D.
Jacobson
,
I.
Kaliman
,
R. Z.
Khaliullin
,
T.
Kuś
,
A.
Landau
,
J.
Liu
,
E. I.
Proynov
,
Y. M.
Rhee
,
R. M.
Richard
,
M. A.
Rohrdanz
,
R. P.
Steele
,
E. J.
Sundstrom
,
H. L.
Woodcock
,
P. M.
Zimmerman
,
D.
Zuev
,
B.
Albrecht
,
E.
Alguire
,
B.
Austin
,
G. J. O.
Beran
,
Y. A.
Bernard
,
E.
Berquist
,
K.
Brandhorst
,
K. B.
Bravaya
,
S. T.
Brown
,
D.
Casanova
,
C.-M.
Chang
,
Y.
Chen
,
S. H.
Chien
,
K. D.
Closser
,
D. L.
Crittenden
,
M.
Diedenhofen
,
R. A.
DiStasio
,
H.
Do
,
A. D.
Dutoi
,
R. G.
Edgar
,
S.
Fatehi
,
L.
Fusti-Molnar
,
A.
Ghysels
,
A.
Golubeva-Zadorozhnaya
,
J.
Gomes
,
M. W. D.
Hanson-Heine
,
P. H. P.
Harbach
,
A. W.
Hauser
,
E. G.
Hohenstein
,
Z. C.
Holden
,
T.-C.
Jagau
,
H.
Ji
,
B.
Kaduk
,
K.
Khistyaev
,
J.
Kim
,
J.
Kim
,
R. A.
King
,
P.
Klunzinger
,
D.
Kosenkov
,
T.
Kowalczyk
,
C. M.
Krauter
,
K. U.
Lao
,
A. D.
Laurent
,
K. V.
Lawler
,
S. V.
Levchenko
,
C. Y.
Lin
,
F.
Liu
,
E.
Livshits
,
R. C.
Lochan
,
A.
Luenser
,
P.
Manohar
,
S. F.
Manzer
,
S.-P.
Mao
,
N.
Mardirossian
,
A. V.
Marenich
,
S. A.
Maurer
,
N. J.
Mayhall
,
E.
Neuscamman
,
C. M.
Oana
,
R.
Olivares-Amaya
,
D. P.
O’Neill
,
J. A.
Parkhill
,
T. M.
Perrine
,
R.
Peverati
,
A.
Prociuk
,
D. R.
Rehn
,
E.
Rosta
,
N. J.
Russ
,
S. M.
Sharada
,
S.
Sharma
,
D. W.
Small
,
A.
Sodt
,
T.
Stein
,
D.
Stück
,
Y.-C.
Su
,
A. J. W.
Thom
,
T.
Tsuchimochi
,
V.
Vanovschi
,
L.
Vogt
,
O.
Vydrov
,
T.
Wang
,
M. A.
Watson
,
J.
Wenzel
,
A.
White
,
C. F.
Williams
,
J.
Yang
,
S.
Yeganeh
,
S. R.
Yost
,
Z.-Q.
You
,
I. Y.
Zhang
,
X.
Zhang
,
Y.
Zhao
,
B. R.
Brooks
,
G. K. L.
Chan
,
D. M.
Chipman
,
C. J.
Cramer
,
W. A.
Goddard
,
M. S.
Gordon
,
W. J.
Hehre
,
A.
Klamt
,
H. F.
Schaefer
,
M. W.
Schmidt
,
C. D.
Sherrill
,
D. G.
Truhlar
,
A.
Warshel
,
X.
Xu
,
A.
Aspuru-Guzik
,
R.
Baer
,
A. T.
Bell
,
N. A.
Besley
,
J.-D.
Chai
,
A.
Dreuw
,
B. D.
Dunietz
,
T. R.
Furlani
,
S. R.
Gwaltney
,
C.-P.
Hsu
,
Y.
Jung
,
J.
Kong
,
D. S.
Lambrecht
,
W.
Liang
,
C.
Ochsenfeld
,
V. A.
Rassolov
,
L. V.
Slipchenko
,
J. E.
Subotnik
,
T.
Van Voorhis
,
J. M.
Herbert
,
A. I.
Krylov
,
P. M. W.
Gill
, and
M.
Head-Gordon
, “
Advances in molecular quantum chemistry contained in the Q-Chem 4 program package
,”
Mol. Phys.
113
,
184
215
(
2015
).
83.
R.
Ditchfield
,
W. J.
Hehre
, and
J. A.
Pople
, “
Self-consistent molecular-orbital methods. IX. An extended Gaussian-type basis for molecular-orbital studies of organic molecules
,”
J. Chem. Phys.
54
,
724
728
(
1971
).
84.
P. C.
Hariharan
and
J. A.
Pople
, “
The influence of polarization functions on molecular orbital hydrogenation energies
,”
Theor. Chim. Acta
28
,
213
222
(
1973
).
85.
W. J.
Hehre
,
R.
Ditchfield
, and
J. A.
Pople
, “
Self—Consistent molecular orbital methods. XII. Further extensions of Gaussian—Type basis sets for use in molecular orbital studies of organic molecules
,”
J. Chem. Phys.
56
,
2257
2261
(
1972
).
86.
T. J. A.
Wolf
,
R. H.
Myhre
,
J. P.
Cryan
,
S.
Coriani
,
R. J.
Squibb
,
A.
Battistoni
,
N.
Berrah
,
C.
Bostedt
,
P.
Bucksbaum
,
G.
Coslovich
,
R.
Feifel
,
K. J.
Gaffney
,
J.
Grilj
,
T. J.
Martinez
,
S.
Miyabe
,
S. P.
Moeller
,
M.
Mucke
,
A.
Natan
,
R.
Obaid
,
T.
Osipov
,
O.
Plekan
,
S.
Wang
,
H.
Koch
, and
M.
Guhr
, “
Probing ultrafast pi pi*/n pi* internal conversion in organic chromophores via K-edge resonant absorption
,”
Nat. Commun.
8
,
29
(
2017
).
87.
J. D.
Coe
and
T. J.
Martínez
, “
Competitive decay at two- and three-state conical intersections in excited-state intramolecular proton transfer
,”
J. Am. Chem. Soc.
127
,
4560
4561
(
2005
).
88.
D.
Jacquemin
,
V.
Wathelet
,
E. A.
Perpète
, and
C.
Adamo
, “
Extensive TD-DFT benchmark: Singlet-excited states of organic molecules
,”
J. Chem. Theory Comput.
5
,
2420
2435
(
2009
).
89.
T.
Risthaus
,
A.
Hansen
, and
S.
Grimme
, “
Excited states using the simplified Tamm–Dancoff-approach for range-separated hybrid density functionals: Development and application
,”
Phys. Chem. Chem. Phys.
16
,
14408
14419
(
2014
).
90.
S.
Grimme
and
C.
Bannwarth
, “
Ultra-fast computation of electronic spectra for large systems by tight-binding based simplified Tamm–Dancoff approximation (sTDA–xTB)
,”
J. Chem. Phys.
145
,
054103
(
2016
).
91.
A.
Hellweg
,
S. A.
Grün
, and
C.
Hättig
, “
Benchmarking the performance of spin-component scaled CC2 in ground and electronically excited states
,”
Phys. Chem. Chem. Phys.
10
,
4119
4127
(
2008
).
92.
F.
Furche
,
R.
Ahlrichs
,
C.
Hättig
,
W.
Klopper
,
M.
Sierka
, and
F.
Weigend
, “
Turbomole
,”
Wiley Interdiscip. Rev.: Comput. Mol. Sci.
4
,
91
100
(
2014
).
93.
C.
Song
and
T. J.
Martínez
, “
Reduced scaling CASPT2 using supporting subspaces and tensor hyper-contraction
,”
J. Chem. Phys.
149
,
044108
(
2018
).
94.
D.
Asturiol
,
B.
Lasorne
,
M. A.
Robb
, and
L.
Blancafort
, “
Photophysics of the π, π* and n, π* states of thymine: MS-CASPT2 minimum-energy paths and CASSCF on-the-fly dynamics
,”
J. Phys. Chem. A
113
,
10211
10218
(
2009
).
95.
J.
Segarra-Martí
,
A.
Francés-Monerris
,
D.
Roca-Sanjuán
, and
M.
Merchán
, “
Assessment of the potential energy hypersurfaces in thymine within multiconfigurational theory: CASSCF vs. CASPT2
,”
Molecules
21
,
1666
(
2016
).

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