Fi s P inciples S udy o Nickel Complex wi h 1,3-di hiole-2- hione-4,5-di hiola e
Ligands as Model Pho osensi ize s
L. W. C. Paes,1 J. Amaya Suá ez,2 A. M. Má quez and Ja ie . Fdez. Sanz2*
1 Depa amen o de Ciências Exa as, Escola de Engenha ia Indus ial e Me alu gia de
Vol a Redonda, 27255-125, Vol a Redonda, RJ, B azil
2 Depa amen o de Química Física, Facul ad de Química, Uni e sidad de Se illa, E-
41012 Se illa, Spain
Abs ac
Dye-sensi ized sola cells (DSSCs) ha e become in one impo an and p omising
echnology in he pho o ol aic ield. The abili y o a sensi ize o ha es ligh pho ons
and injec he exci ed elec ons in o a pho oanode, ypically a me al oxide, de e mines
he pe o mance and ope a ion ange o he sola cell. Me al complexes wi h 1,3-
di hiole-2- hione-4,5-di hiola e (dmi ) ligands, which a e an impo an class o
unc ional ma e ials, ha e ecei ed ex ensi e a en ion due o hei in iguing chemical
and physical p ope ies. The elec onic and molecula p ope ies o isola ed and
adso bed nickel complexes wi h dmi ligands ha e been in es iga ed using i s
p inciples calcula ions based on he densi y unc ional heo y (DFT). Adso p ion
ene gies o me al complexes suppo ed on he ana ase TiO2(101) su ace we e
calcula ed o h ee di e en con igu a ions, linked by sulphu a om o S hione, S hiole-
S hiola e, and plana . The mos s able adso p ion con igu a ions ound in his s udy a e he
S hiole-S hiola e and he plana o ms o he nickel complex. TD-DFT molecula
calcula ions e eal ha he lowes ene gy ansi ion in ul a iole isible nea -in a ed
(UV-Vis-NIR) mainly co esponds o he HOMO-LUMO π–π* exci a ion o he nickel
complex. The e ec o he TiO2(101) su ace on he abso p ion spec a o he nickel
complex is p ac ically limi ed o a ed shi o abou 0.1-0.3 eV. The analysis o he
densi y o s a es o he dmi /TiO2(101) sys em shows ha he LUMO o he me al
complex lies a he edge o he TiO2 conduc ion band indica ing, he e o e, ha elec on
injec ion om he complex exci ed s a e in o he semiconduc o su ace is unlikely.
Keywo ds: Me al complexes, dmi ligand, DFT, TD-DFT, Adso p ion ene gy, Sensi ize
1
In oduc ion
The sensi iza ion o wide band-gap semiconduc o s lays a he hea o dye
sensi ized sola cells (DSSCs), a ising echnology o sola ene gy ha es ing ha
o e s some ad an ages o e classical Si-based de ices[1, 2]. A key s eng h o DSSCs
is he sepa a ion o elec on gene a ion and anspo p ocesses in wo dis inc ma e ials.
This allows he disconnec ed op imiza ion o he dye o pho on abso p ion and o a
wide band-gap semiconduc o o elec on-hole sepa a ion and collec ion [3].
Typically me al oxides like zinc oxide (ZnO)[4, 5], s annic oxide (SnO2)
[6, 7, 8] and i anium dioxide (TiO2) [2] ha e been used as he semiconduc o ma e ial.
Howe e , di e en expe imen al esul s ha e shown ha TiO2 is p e e able o e ei he
ZnO o SnO2. Ti anium dioxide is non- oxic, highly abundan , and p o ides a
mesopo ous s uc u e o bo h o ganic and ino ganic dye adso p ion.
The ole o he dye is o abso b he incoming pho ons and o ans e he exci ed
elec on o he conduc ion band o he semiconduc o . Thus, an e icien dye should (a)
be s ongly adso bed a he semiconduc o su ace; (b) show in ense abso p ion in he
isible and nea in a ed egions o he elec omagne ic spec um; (c) be s able enough
as o be capable o mul iple oxida ion- educ ion cycles and (d) be s able enough in i s
oxidized o m as o be educed by he elec oly e and his lowes exci ed s a e should be
highe han he semiconduc o conduc ion band edge.
Basically, pho osensi ize dyes a e ei he pu e o ganic compounds o
me al-based o ganome allic complexes. Me al- ee o ganic sensi ize s a e cheape , easy
o modi y s uc u ally o une he dye p ope ies, in some cases hey a e en i onmen ally
benign and non- oxic and ha e high mola abso p ion coe icien s. Howe e , hey also
show impo an s abili y and e iciency p oblems. Many me al complexes-based dyes
ha e been p oposed. O hese, u henium (II) polypy idyl complexes ha e been shown
o be he bes so a [9]. Howe e , he low abundance o he me al, i s high cos and
oxici y impose se e e limi a ions on i s p ac ical and widesp ead use. Thus, ansi ion
me al complexes based on i on (Fe), nickel (Ni), cobal (Co), palladium (Pd), pla inum
(P ), and zinc (Zn), among o he s, ha e been p oposed as al e na i es in he design o
pho o ol aic sensi ize s [2,3,10,11,12,13,14].
In his ega d, squa e-plana complexes wi h sul u -con aining ligands ha
abso b in he nea in a ed egion (NIR) o he spec um ha e a ac ed special in e es
and ha e been examined bo h expe imen ally and heo e ically [12,15,16,17,18,19].
Islam e al. [15] we e he i s o explo e he applica ion o a se ies o squa e-plana
2
diimine-di hiola e complexes as sensi ize s. They syn hesized and cha ac e ized a se ies
o pla inum-based polypy idyl complexes wi h di hiola e ligands ha we e also
ancho ed o nanoc ys alline TiO2 in pho oelec ochemical cells. The in ense cha ge
ans e band in hese complexes was shown o be unable by changing he di hiola e
ligands. Gea y e al. [16] p epa ed and examined a amily o P (II)(diimine)(di hiola e)
complexes, analyzing he in luence o 3,3’-, 4,4’-, and 5,5’- bipy idyl subs i uen s on
hei elec onic p ope ies. All syn hesized complexes whe e a ached o a TiO2
subs a e and es ed as sola cells sensi ize s wi h he 3,3’-disus i u ed bipy idyl
complex showing he highes pho o ol aic pe o mance.
In a la e s udy [17] he supe io pe o mance o he 3,3’- bipy idyl complex was
a ionalized by using densi y unc ional heo y calcula ions based on a hyb id unc ional
ha sugges ed ha he longe -li ed cha ge-sepa a ed s a e o his complex on TiO2 was
ela ed o he non-plana geome y o he complex, educing he elec onic coupling
be ween ligands. Laza ides e al. [18] ha e a emp ed o inc ease he ligh abso p ion
p ope ies o P (II)(diimine)(di hiola e) ch omopho es by combining hem wi h
bo on-dipy ome hene, a s ongly abso bing dye, in a dual ch omopho e sys em. By
using ime-dependen DFT calcula ions, he au ho s show ha he many pa hs o
elec on ans e ha exis in hese sys ems esul in unexpec ed ou es o exci ed-s a e
elaxa ion and loss o he desi ed p ope ies o he exci ed cha ge ans e s a e. Despi e
he in ense wo k de eloped on examining he po en ial o P (II)(diimine)(di hiola e)
complexes as sensi ize s o DSSC cells, only he pape by Lin oo e al. [12] has
s udied some Ni(II)(diimine)(di hiola e) dyes in ela ion wi h hei use as dyes in a
DSSC cell. The au ho s cha ac e ized he complexes using elec ochemical,
spec oscopic and compu a ional echniques and assigned in ense isible abso p ions o
ligand- o-ligand cha ge ans e ansi ions ha would sugges app op ia e cha ge
sepa a ion o using on a pho oelec ochemical de ice. Howe e , low pho ocu en s
we e ound when he complex was adso bed on a TiO2 ilm, a p oblem ha was linked
o a sho -li ed exci ed s a e o he Ni(II) complex.
Because o hei unique p ope ies ela ed o applica ions in ields as di e se as
conduc ing and supe conduc ing ma e ials, non-linea op ics, ca alysis, and dyes, me al
di hiolene complexes, R2M(dmi )2, R=PyMe, NE 4, NMe4, NP 4, NBu4, and dmi =1,3-
di hiole-2- hione-4,5-di hiola e) ha e been ex ensi ely s udied o mo e han o y yea s
[20]. These applica ions esul om an in e play o di e en p ope ies, including
highly delocalized on ie o bi als ha allow di ec elec on ans e h ough he ligand
3
π o bi als. Fo his eason, hese complexes a e conside ed p omising candida es o
pho ochemical de ices [21].
He e, we p esen a s udy o he s uc u al and spec oscopic p ope ies o he
model di hiolene complex [(CH3)2][Ni(dmi )2] by combining DFT and TD-DFT
calcula ions. Fi s we analyze he p ope ies o he isola ed complex using he B3LYP
unc ional and an a om-cen e ed basis se . Second, he geome ic and elec onic
p ope ies o he complex adso bed on a model TiO2 (101) ana ase su ace ha e been
examined by using plane-wa e calcula ions ha include bo h he use o a Hubba d
co ec ion o p ope ly localize he me al d-elec ons and an app oxima e unc ional o
imp o e he desc ip ion o he dispe sion o ces on he DFT calcula ions. Finally, we
heo e ically examine he pe o mance o he model [(CH3)2][Ni(dmi )2] complex as a
sensi ize .
Compu a ional de ails
Fo he isola ed [CH3]2[Ni(dmi )2] complex, DFT calcula ions ha e been
pe o med using he Gaussian 09 quan um chemical package [22]. Equilib ium
geome y and elec onic p ope ies we e de e mined by employing he hyb id Becke
h ee-pa ame e unc ional wi h he Lee, Yang, and Pa (B3LYP) exchange co ela ion
unc ional [23,24], wi h CEP-121G [25,26,27] e ec i e co e po en ials and basis se s
o Ni and S a oms and 6-31++G basis se o C and H a oms. Gi en ha some cha ge-
ans e cha ac e was ound in he i s exci ed s a e, he CAM-B3LYP hyb id
unc ional, ha includes long- ange co ec ions was also employed [28]. TD-DFT
single-poin ene gy calcula ions we e pe o med on op imized geome ies.
To de e mine he geome ic and elec onic p ope ies o he TiO2 (101) su ace
and TiO2 (101) su ace wi h he adso bed nickel complex, we pe o med pe iodic DFT
calcula ions using he Vienna ab ini io Simula ion Package (VASP) [29,30,31]. The
p ojec o augmen ed wa e (PAW) me hod was used, and he cu o ene gy was se o
400 eV o slab and adso p ion calcula ions. The gene alized g adien app oxima ion
(GGA) unc ional was used (Pe dew-Bu ke-E nze ho , PBE) [32]. In o de o be e
ende he ana ase band gap, usually unde es ima ed in plain GGA DFT calcula ions, a
Hubba d ype on-si e Coulomb co ec ion e m was used as implemen ed by Duda e e
al. [33]. The GGA+U p ocedu e was applied on he ansi ion me al d elec ons, being
he 𝑈e alues employed in his wo k 4.5 eV and 5.5 eV o 3d le els o Ti and Ni,
4
espec i ely [34,35]. Op ical spec a we e ob ained om he equency dependen
dielec ical unc ions as p oposed by Gajdoš e al. [36].
Because GGA unc ionals neglec a ac i e long- ange con ibu ions, compu ed
adso p ion ene gies a e gene ally unde es ima ed [37]. To include he an de Waals
co ec ions in o he densi y unc ional app oach ( dW-DF) and ob ain a mo e accu a e
desc ip ion, he me hod p oposed by Tka chenko and Sche le was employed in his
wo k [38].
The slab model o ana ase su ace was ob ained by app op ia ely cu ing he
mos s able TiO2 (101) su ace, and is ep esen ed by 96 [TiO2] uni s a anged
acco ding o ana ase c ys alline s uc u e. The model 5x3 supe cell consis ed o wo
O-Ti-O ilaye s, 144 a oms each, whe e he bo om laye was ixed. The o ho hombic
supe cell has, hus, dimensions: a = 31.254 Å, b = 15.288 Å and c = 35.916 Å,
including a acuum space o 20 Å in he c di ec ion. All calcula ions we e pe o med a
he Γ poin .
Adso p ion o [CH3]2[Ni(dmi )2] complex on he TiO2 (101) su ace was done
in h ee di e en adso p ion con igu a ions: linked by S hione, linked by S hiole-S hiola e
(b idge) and plane (Fig. 1).
Fig. 1: Schema ic s uc u e o adso p ion o m S hione, S hiole-S hiola e.
Adso p ion ene gies (𝐸𝐴𝐷𝑆 ) o he op imized me al complexes on he TiO2(101)
su ace we e calcula ed using
𝐸𝐴𝐷𝑆 =𝐸(TiO2)+(Nidmi )− (𝐸(TiO2)+ 𝐸Nidmi )
whe e 𝐸(TiO2)+(Nidmi ) is he ene gy o (Ni-dmi ) complex adso bed on he TiO2 (101)
su ace, 𝐸Nidmi R and 𝐸(TiO2)R a e he ene gies o he isola ed Ni-dmi complex and clean
TiO2 (101) su ace espec i ely. Wi h his de ini ion, nega i e adso p ion ene gies
ep esen bound s a es s able wi h espec o deso p ion.
5

Resul s and discussion
S uc u e and Elec onic P ope ies o [CH3]2[Ni(dmi )2] complex
Fig. 2 shows he op imized s uc u e o he squa e plana complex
[CH3]2[Ni(dmi )2]. Table 1 p esen s he geome ic pa ame e s ob ained a he B3LYP
and PBE+U le els, in compa ison o he expe imen al s uc u e. We epo only he
ele an bond leng hs and bond angles.
Fig. 2:
Op imized s uc u e o [CH
3
]
2
[Ni(dmi )
2
] complex. A oms colo s code:
Ni, g ay; C, black; S, yellow; H, whi e.
Table 1: Main geome ical pa ame e s calcula ed o [CH3]2[Ni(dmi )2] complexes
B3LYP CAM-B3LYP PBE+U Exp [39]
Bond dis ances
Ni-S
2.244
2.230
2.186
2.16-2.17
S=C
1.747
1.749
1.721
1.66
C=C
1.401
1.400
1.416
1.39
Bond angles
S-Ni-S
92.6
92.8
93.1
92.2
S-Ni-S
87.4
87.2
93.2
86.6
Ni-S-C
101.5
101.4
102.4
102.8
*Bond leng hs in Å and bond angles in deg ees
F om he da a shown in Table 1, a gene al ag eemen be ween calcula ed and
expe imen al alues is obse ed. Op imized bond dis ances a e sys ema ically
o e es ima ed, and he alues ob ained om PBE+U calcula ions in gene al a e in be e
6
ag eemen han hose es ima ed wi h ei he he B3LYP o he CAM-B3LYP unc ionals,
excep o he C=C double bond. Ni–S bond leng hs a e e y simila o each o he and
in ag eemen wi h he expe imen al esul s. In con as , he S=C bond is signi ican ly
o e es ima ed. The disag eemen ound can be ela ed o he ac ha expe imen al da a
de i e om solid c ys al s uc u e di ac ion expe imen s in which packing o ces may
al e he geome y o indi idual molecules.
The calcula ed ha monic ib a ional equencies and band assignmen s o he
nickel complex a e p esen ed in Table 2.
Table 2: Compa ison be ween he expe imen al and calcula ed equencies and
assignmen s o ib a ional modes o [CH3]2[Ni(dmi )2] (cm-1)
The calcula ed peaks associa ed wi h he C-H s e ch modes o he [CH3] g oups
we e ound a 3073/3098/3001 cm−1 o B3LYP, CAM-B3LYP and PBE+U
espec i ely. The bands a 1331/1374/1297 cm−1 and 993/1063/950 cm−1 we e assigned
o C=C and C=S s e ching modes, espec i ely, and we e compa ible wi h o he
published esul s [40]. Valade e al. [41] also epo ed he C=C peak a 1430 cm-1, and
lis ed wo peaks a 455 cm-1 and 310 cm-1; bo h we e assigned as Ni-S ib a ion. The
bands a 496/509/490 cm-1 a e cha ac e is ic o he undamen al ib a ions o he
hioca bona e g oup (–S–(C=S hione)-S–). The C=S s e ching ib a ion is he
cha ac e is ic ib a ion in he IR spec a o DMIT complexes. Acco ding o a ious
B3LYP
CAM-
B3LYP
PBE+U
Exp
[40,41,42,43,44
]
υ
s
(C-H)
3073
3098
3001
3000
υ
s
(C=C)
1331
1374
1297
1454
υ(C-S
hiole
)
943
984
933
940
υ(S-(C=S
hione
)-S)
496
509
490
531
υ(C=S) + υ(S
hiole
-C
hione
-S
hiole
)
993
1063
950
1039
υ(Ni-S
hiola e
)
418
438
414
455
υ(Ni-S
hiola e
)
317
337
318
310
7
au ho s, se e al peaks appea in he 1050-995 cm−1 ange, making i di icul o assign
as C=S [42,43]. The esul s show he same endency o di e en le els o calcula ions
in desc ibing he ib a ional p ope ies.
Conside ing now he elec onic p ope ies o me al complexes we i s s a
analyzing he HOMO and LUMO Kohn–Sham on ie o bi als o [CH3]2[Ni(dmi )2].
As can be seen in Fig. 3, he HOMO is o π-cha ac e and mainly co esponds o he
C2S22− uni o dmi ligand and Ni(II) d o bi al cen e . The LUMO is mainly con ibu ed
om he hiole ing o dmi ligand wi hou me al pa icipa ion. The same p o ile was
obse ed by Fan e al. [45].
Fig. 3:
Kohn–Sham on ie o bi als o isola ed [CH
3
]
2
[Ni(dmi )
2
] HOMO (le );
LUMO ( igh ).
Abso p ion elec onic spec a we e ob ained om TD-DFT calcula ions
pe o med a he op imized g ound-s a e geome ies (Fig. 4). Calcula ed oscilla o
s eng hs, ansi ion ene gies, and wa e unc ion o he mos ele an ansi ions o
elec onic abso p ion bands a e lis ed in Table 3. The in luence o he sol en
en i onmen on he abso p ion spec a was no conside ed in ou calcula ions. Only
ansi ions wi h signi ican oscilla o s eng hs a e p esen ed. Fi y single elec onic
exci ed s a es we e included.
8
Table 3: Exci a ion ene gy (E in eV), oscilla o s eng h (ƒ) and main con igu a ions o
he wa e unc ion o [CH3]2[Ni(dmi )2] a TDDFT/B3LYP and TDDFT/CAM-B3LYP
le els o heo y (H=HOMO, L=LUMO).
B3LYP
CAM-B3LYP
E
ƒ
Main con igu a ions
E
Main con igu a ions
1.51
0.33
H→L
2.03
0.50
H→L/H-1→L+1
2.49
0.12
H-1→L+1
3.35
0.07
H→L/H-1→L+1
3.29
0.08
H-6→L
4.69
0.15
H-7→L
3.97
0.04
H→L+5/H→L+8
4.79
0.54
H-5→L+2
4.32
0.60
H-5→L+2/H→L+8/H→L+10
Fig 4.:
Gas phase UV- is abso p ion spec um o [CH
3
]
2
[Ni(dmi )
2
] compu ed a
he TDDFT/B3LYP and TDDFT/CAM-B3LYP le els o heo y.
As shown bo h in Table 3 and Fig. 4, he heo e ical desc ip ion o he UV- is
abso p ion spec um o [CH3]2[Ni(dmi )2] complex is, quan i a i ely, qui e di e en o
he wo DFT unc ionals es ed. The i s abso p ion appea s a a wa eleng h
o  800 nm when he B3LYP unc ional is used, Howe e , he CAM-B3LYP unc ional
o e s a di e en pic u e, wi h a i s , qui e in ense band appea ing a  590 nm, in much
9
Re e ences
1. Nazee uddin MK, Ba ano E, G ä zel M (2011) Dye-sensi ized sola cells: A b ie
o e iew, Sol Ene gy 85:1172-1178
2. Hag eld A, Boschloo G, Sun L, Kloo L, Pe e sson H (2010) Dye-Sensi ized Sola
Cells, Chem Re 110:6595-6663
3. Robe son N (2006) Op imizing Dyes o Dye ‐
Sensi ized Sola Cells, An
gew Chem
In Edi 45:2338-2345
4. Lupan O, Gué in VM, Tiginyanu IM, U saki VV, Chow L, Hein ich H, Paupo é T
(2010) Well-aligned a ays o e ically o ien ed ZnO nanowi es elec odeposi ed on
ITO-coa ed glass and hei in eg a ion in dye sensi ized sola cells, J Pho och Pho obio
A 211:65-73
5. Sakai N, Miyasaka T, Mu akami TN (2013) E iciency Enhancemen o ZnO-Based
Dye-Sensi ized Sola Cells by Low-Tempe a u e TiCl4 T ea men and Dye
Op imiza ion, J Phys Chem C 117:10949-10956
6. Han DW, Heo JH, Kwak DJ, Han CH, Sung, YM (2009) Tex u e, Mo phology and
Pho o ol aic Cha ac e is ics o Nanopo ous F:SnO2 Films, J Elec Eng Technol 4:93-
97
7. Fe e e S, Zaban A, G egg BA (1997) Dye Sensi iza ion o Nanoc ys alline Tin
Oxide by Pe ylene De i a i es, J Phys Chem B 101:4490-4493
8. Niu H, Zhang S, Wang R, Guo Z, Shang X, Gan W, Qin S, Wan L, Xu J (2014) Dye-
Sensi ized Sola Cells Employing a Mul i unc ionalized Hie a chical SnO2 Nano lowe
S uc u e Passi a ed by TiO2 Nanog anulum, J Phys Chem C 118:3504-3513
9. Nazee uddin MK, De Angelis F, Fan acci S, Selloni A, Visca di G, Liska P, I o S,
Take u B, G ä zel M (2005) Combined Expe imen al and DFT-TDDFT Compu a ional
S udy o Pho oelec ochemical Cell Ru henium Sensi ize s, J Am Chem Soc 127:16835-
16847
10. Yella A, Lee HW, Tsao HN, Yi C, Chandi an AK, Nazee uddin MK, Diau EWG,
Yeh CY, Zakee uddin SM, G ä zel M (2011) Po phy in-Sensi ized Sola Cells wi h
Cobal (II/III)–Based Redox Elec oly e Exceed 12 Pe cen E iciency, Science
334:629-634
11. Diwan K, Chauhan R, Singh SK, Singh B, D ew MGB, Bahadu L, Singh N (2014)
Ligh ha es ing p ope ies o some new he e olep ic di hioca bima e-diamine/diimine
complexes o Ni, Pd and P s udied as pho osensi ize in dye-sensi ized TiO2 sola cells,
New J Chem 38:97-108
12. Lin oo CL, Richa dson P, McCall KL, Du an JR, Mo andei a A, Robe son N
(2011) A nickel-complex sensi ise o dye-sensi ised sola cells, Sol Ene gy 85:1195-
1203
13. Duchanois T, Thibaud E, Ceb ián C, Lui L, Mona i A, Baley M, Ass eld X, Haacke
S, G oss PC (2015) An I on-Based Pho osensi ize wi h Ex ended Exci ed-S a e
Li e ime: Pho ophysical and Pho o ol aic P ope ies, Eu J Ino g Chem 14:2469-2477
16

14. Duchanois T, E ienne T, Beley M, Ass eld X, Pe pè e EA, Mona i A, G os PC
(2014) He e olep ic Py idyl-Ca bene I on Complexes wi h Tuneable Elec onic
P ope ies, Eu J Ino g Chem 23:3747-3753.
15. Islam A, Sugiha a H, Ha a K, Singh LP, Ka oh R, Yanagida M, Takahashi Y,
Mu a a S, A akawa H, Fujihashi G (2001) Dye Sensi iza ion o Nanoc ys alline
Ti anium Dioxide wi h Squa e Plana Pla inum(II) Diimine Di hiola e Complexes, Ino g
Chem 40:5371-5380
16. Gea y EAM, Yellowlees LJ, Jack LA, Oswald IDH, Pa sons S, Hi a a N, Du an
JR, Robe son N (2005) Syn hesis, S uc u e, and P ope ies o
[P (II)(diimine)(di hiola e)] Dyes wi h 3,3‘-, 4,4‘-, and 5,5‘-Disubs i u ed Bipy idyl:
Applica ions in Dye-Sensi ized Sola Cells, Ino g Chem 44:242-250
17. Gea y EAM, McCall KL, Tu ne A, Mu ay PR, McInnes EJL, Jack LA, Yellowlees
LJ, Robe son N (2008) Spec oscopic, elec ochemical and compu a ional s udy o P -
diimine-di hiolene complexes: a ionalising he p ope ies o sola cell dyes, Dal on
T:3701-3708
18. Laza ides T, McCo mick TM, Wilson KC, Lee S, McCaman DW, Eisenbe g R
(2011) Sensi izing he Sensi ize : The Syn hesis and Pho ophysical S udy o
Bodipy−P (II)(diimine)(di hiola e) Conjuga es, J Am Chem Soc 133:350-364
19. B owning C, Hudson JM, Reinheime EW, Kuo FL, McDougaldJ RN, Rabaâ H,
Pan H, Bacsa J, Wang X, Dunba KR, Shephe d ND, Oma y MA (2014) Syn hesis,
Spec oscopic P ope ies, and Pho oconduc i i y o Black Abso be s Consis ing o
P (Bipy idine)(Di hiola e) Cha ge T ans e Complexes in he P esence and Absence o
Ni o luo enone Accep o s, J Am Chem Soc 136:16185-16200
20. Ka o R (2004) Conduc ing Me al Di hiolene Complexes:  S uc u al and Elec onic
P ope ies, Chem Re 104:5319-5346
21. Za kadoulas A, Kou sou i E, Mi sopoulou CA (2012) A pe spec i e on sola ene gy
con e sion and wa e pho ospli ing by di hiolene complexes. Coo dina ion Chemis y
Re iews 256:2424-2434
22. F isch MJ, T ucks GW, Schlegel HB, Scuse ia GE, Robb MA, Cheeseman JR,
Scalmani G, Ba one V, Mennucci B, Pe e sson GA, Naka suji H, Ca ica o M, Li X,
H a chian HP, Izmaylo AF, Bloino J, Zheng G, Sonnenbe g JL, Hada M, Eha a M,
Toyo a K, Fukuda R, Hasegawa J, Ishida M, Nakajima T, Honda Y, Ki ao O, Nakai H,
V e en T, Mon gome y J JA, Pe al a JE, Oglia o F, Bea pa k M, Heyd JJ, B o he s E,
Kudin KN, S a o e o VN, Kei h T, Kobayashi R, No mand J, Ragha acha i K,
Rendell A, Bu an JC, Iyenga SS, Tomasi J, Cossi M, Rega N, Millam JM, Klene M,
Knox JE, C oss JB, Bakken V, Adamo C, Ja amillo J, Gompe s R, S a mann RE,
Yazye O, Aus in AJ, Cammi R, Pomelli C, Och e ski JW, Ma in RL, Mo okuma K,
Zak zewski V G, Vo h GA, Sal ado P, Dannenbe g JJ, Dapp ich S, Daniels AD,
Fa kas O, Fo esman JB, O iz JV, Cioslowski J, Fox DJ, (2010) Gaussian, Inc., CT
Walling o d CT
23. Lee C, Yang W, Pa RG, (1988) De elopmen o he Colle-Sal e i co ela ion-
ene gy o mula in o a unc ional o he elec on densi y, Phys Re B 37:785
17
24. Becke AD, (1988) Densi y- unc ional exchange-ene gy app oxima ion wi h co ec
asymp o ic beha io , Phys Re A 38:3098
25. S e ens WJ, Basch H, K auss M, (1984) Compac e ec i e po en ials and e icien
sha ed ‐
exponen basis se s o he i s ‐ and s
ow a oms, J Chem Phys
81:6026
26. S e ens WJ, K auss M, Basch H, Jasien PG, (1992) Rela i is ic compac e ec i e
po en ials and e icien , sha ed-exponen basis se s o he hi d-, ou h-, and i h- ow
a oms, Can J Chem 70:612-630
27. Cunda i TR, S e ens WJ, (1993) E ec i e co e po en ial me hods o he
lan hanides, J Chem Phys 98:5555
28. Yanai T, Tew DP, Handy NC (2004) A new hyb id exchange-co ela ion unc ional
using he Coulomb-a enua ing me hod (CAM-B3LYP), Chem Phys Le 393:51
29. K esse G, Ha ne J, (1993) Ab ini io molecula dynamics o liquid me als, Phys
Re B 47:558
30. K esse G, Fu hmülle J, (1996) E icien i e a i e schemes o ab ini io o al-ene gy
calcula ions using a plane-wa e basis se , Phys Re B 54:11169
31. K esse G, Fu hmülle J, (1996) E iciency o ab-ini io o al ene gy calcula ions o
me als and semiconduc o s using a plane-wa e basis se , Comp Ma Sci 6:15-50
32. Pe dew JP, Bu ke K, E nze ho M, (1996) Gene alized G adien App oxima ion
Made Simple, Phys Re Le 77: 3865
33. Duda e SL, Bo on GA, Sa aso SY, Humph eys CJ, Su on AP, (1998) Elec on-
ene gy-loss spec a and he s uc u al s abili y o nickel oxide: An LSDA+U s udy, Phys
Re B 57:1505
34. Calzado CJ, He nández NC, Sanz JF, (2008) E ec o on-si e Coulomb epulsion
e m U on he band-gap s a es o he educed u ile (110) TiO2 su ace, Phys Re B
77:045118
35. Cao C, Hill S, Cheng HP, (2008) S ongly Co ela ed Elec ons in he
[Ni(hmp)(ROH)X]4 Single Molecule Magne : A DFT+U S udy, Phys Re Le
100:167206
36. Gajdoš M, Humme K, K esse G, Fu hmülle J, Bechs ed F (2006) Linea op ical
p ope ies in he p ojec o -augmen ed wa e me hodology Phys Re B 73:045112
37. Klimeš J, Bowle DR, Michaelides A, (2011) Van de Waals densi y unc ionals
applied o solids, Phys Re B 83:195131
38. B ei ze JG, Rauch uss TB, (2000) S udies on α-C3S52− (dmi 2−) and i s dinuclea
Ni(II) complex: spec oscopic and s uc u al cha ac e iza ion, Polyhed on 19:1283-2391
39. Bousseau M, Valade L, Leg os JP, Cassoux P, Ga bauskas M, In e an e LV, (1986)
Highly conduc ing cha ge- ans e compounds o e a hia ul alene and ansi ion
me al-"dmi " complexes, J Am Chem Soc 108:1908-1916
18
40. Fe ei a GB, Come la o NM, Wa dell JL, Hollaue E, (2004) Vib a ional spec a o
bis(dmi ) complexes o main g oup me als: IR, Raman and ab ini io calcula ions, J B az
Chem Soc 15:951-963
41. Valade L, Leg os JP, Cassoux P, Kubel F, (1986) Syn hesis, Elec ical Conduc i i y,
and C ys al S uc u e o (AsPh4)0.25 [Ni(dmi )2], Mol C ys Liq C ys 140:335-351
42. Singh JD, Singh HB, (1993) Syn hesis and cha ac e iza ion o [M(dmi )2]2− and
[M(dm )2]2− complexes (M = Se(II) o Te(II); dmi = 4,5-dime cap o-1,3-di hiole-2-
hione and dm = 4,5-dime cap o-1,2-di hiole-3- hione), Polyhed on 12:2849-2856
43. Liu G, Fang Q, Xu W, Chen H, Wang C, (2004) Vib a ion assignmen o ca bon–
sul u bond in 2- hione-1,3-di hiole-4,5-di hiola e de i a i es, Spec ochim Ac a A
60:541-550
44. Be na do da C uz AG, Wa dell JL, Rocco AM, (2006) The decomposi ion kine ics
o [E 4N]2[M(dmi )2] (M = Ni, Pd) in a ni ogen a mosphe e using he mog a ime y,
The mochim Ac a 443:217-224
45. Fan HL, Ren Q, Wang XQ, Li TB, Sun J, Zhang GH, Xu D, Yu G, Sun ZH (2009)
In es iga ion on Thi d-O de Op ical Nonlinea i ies o Two O ganome allic Dmi 2-
Complexes Using Z-Scan Technique, Na u al Science 01:136-141
46. da C uz AGB, Wa dell JL, Rangel MVD, Simão RA., Rocco, A. M. (2007)
P epa a ion and cha ac e iza ion o a polypy ole hyb id ilm wi h [Ni(dmi )2]2−,
bis(1,3-di hiole-2- hione-4,5-di hiola e)nickella e(II), Syn he ic Me 157:80-90
47. Fe ei a GB, Hollaue E, Come la o NM, Wa dell JL, (2006) An expe imen al and
heo e ical s udy o he elec onic spec a o e ae hylammonium [bis(1,3-di hiole-2-
hione-4,5-di hiola o)zinca e(II)], [NE 4]2[Zn(dmi )2], and e ae hylammonium [bis(1,3-
di hiole-2-one-4,5-di hiola o)zinca e(II)], [NE 4]2[Zn(dmio)2], Ino g Chim Ac a
359:1239-1247
48. da C uz, AGB, Wa dell JL, Simão RA, Rocco AM, (2007) P epa a ion, s uc u e
and elec ochemis y o a polypy ole hyb id ilm wi h [Pd(dmi )2]2−, bis(1,3-di hiole-2-
hione-4,5-di hiola e)pallada e(II), Elec ochim Ac a 52:1239-1247
49. A oyo-de Dompablo ME, Mo ales-Ga cía A, Ta a illo M (2011) DFT+U
calcula ions o c ys al la ice, elec onic s uc u e, and phase s abili y unde p essu e o
TiO2 polymo phs, J Chem Phys 135: 054503-054511
50. Nadle R, Sanz JF (2013) Simula ing he Op ical P ope ies o CdSe Clus e s Using
he RT-TDDFT App oach, Theo Chem Acc 132:1342
51. Nadle R, Sanz JF (2015) E ec o Capping Ligands and TiO2 Suppo ing on he
Op ical P ope ies o a (CdSe)13, Clus e , J Phys Chem A 119:1218–1227
52. Amaya Suá ez J, Pla a JJ, Ma quez AM, Sanz JF (2016) S uc u al, elec onic and
op ical p ope ies o coppe , sil e and gold sul ide: a DFT s udy, Theo Chem Acc
135:70
19