We design and synthesize a set of homologous organic molecules by taking advantage of facile and tailorable Suzuki cross coupling reactions to produce triarylbenzene derivatives. By adjusting the number and the arrangement of conjugated rings, the identity of heteroatoms, lengths of fluorinated alkyl chains, and other interaction parameters, we create a library of glassformers with a wide range of properties. Measurements of the glass transition temperature (Tg) show a power-law relationship between Tg and molecular weight (MW), with of the molecules, with an exponent of 0.3 ± 0.1, for Tg values spanning a range of 300–450 K. The trends in indices of refraction and expansion coefficients indicate a general increase in the glass density with MW, consistent with the trends observed in Tg variations. A notable exception to these trends was observed with the addition of alkyl and fluorinated alkyl groups, which significantly reduced Tg and increased the dynamical fragility (which is otherwise insensitive to MW). This is an indication of reduced density and increased packing frustrations in these systems, which is also corroborated by the observations of the decreasing index of refraction with increasing length of these groups. These data were used to launch a new database for glassforming materials, glass.apps.sas.upenn.edu.

1.
M. D.
Ediger
,
C. A.
Angell
, and
S. R.
Nagel
, “
Supercooled liquids and glasses
,”
J. Phys. Chem.
100
,
13200
13212
(
1996
).
2.
C. A.
Angell
,
K. L.
Ngai
,
G. B.
McKenna
,
P. F.
McMillan
, and
S. W.
Martin
, “
Relaxation in glassforming liquids and amorphous solids
,”
J. Appl. Phys.
88
,
3113
(
2000
).
3.
P. G.
Debenedetti
and
F. H.
Stillinger
, “
Supercooled liquids and the glass transition
,”
Nature
410
,
259
267
(
2001
).
4.
C. A.
Angell
, “
Formation of glasses from liquids and biopolymers
,”
Science
267
,
1924
1935
(
1995
).
5.
C. A.
Angell
,
J. M.
Sare
, and
E. J.
Sare
, “
Glass transition temperatures for simple molecular liquids and their binary solutions
,”
J. Phys. Chem.
82
,
2622
2629
(
1978
).
6.
L.-M.
Wang
and
R.
Richert
, “
Glass transition dynamics and boiling temperatures of molecular liquids and their isomers
,”
J. Phys. Chem. B
111
,
3201
3207
(
2007
).
7.
W.
Ping
,
D.
Paraska
,
R.
Baker
,
P.
Harrowell
, and
C. A.
Angell
, “
Molecular engineering of the glass transition: Glass-forming ability across a homologous series of cyclic stilbenes
,”
J. Phys. Chem. B
115
,
4696
4702
(
2011
).
8.
T.
Liu
,
K.
Cheng
,
E.
Salami-Ranjbaran
,
F.
Gao
,
E. C.
Glor
,
M.
Li
,
P. J.
Walsh
, and
Z.
Fakhraai
, “
Synthesis and high-throughput characterization of structural analogues of molecular glassformers: 1,3,5-trisarylbenzenes
,”
Soft Matter
11
,
7558
7566
(
2015
).
9.
J.
Dai
,
S. W.
Chang
,
A.
Hamad
,
D.
Yang
,
N.
Felix
, and
C. K.
Ober
, “
Molecular glass resists for high-resolution patterning
,”
Chem. Mater.
18
,
3404
3411
(
2006
).
10.
V. N.
Novikov
and
E. A.
Rössler
, “
Similar dependence of glass transition temperature on molecular mass in molecular glasses and polymers
,”
AIP Conf. Proc.
1599
,
130
133
(
2014
).
11.
A. L.
Agapov
and
A. P.
Sokolov
, “
Does the molecular weight dependence of Tg correlate to Me?
,”
Macromolecules
42
,
2877
2878
(
2009
).
12.
V. N.
Novikov
and
E. A.
Rössler
, “
Correlation between glass transition temperature and molecular mass in non-polymeric and polymer glass formers
,”
Polymer
54
,
6987
6991
(
2013
).
13.
F.
Krohn
,
C.
Neuber
,
E. A.
Rössler
, and
H.-W.
Schmidt
, “
Organic glasses of high glass transition temperatures due to substitution with nitrile groups
,”
J. Phys. Chem. B
123
,
10286
(
2019
).
14.
S.
Mirigian
and
K. S.
Schweizer
, “
Unified theory of activated relaxation in liquids over 14 decades in time
,”
J. Phys. Chem. Lett.
4
,
3648
3653
(
2013
).
15.
S.
Mirigian
and
K. S.
Schweizer
, “
Elastically cooperative activated barrier hopping theory of relaxation in viscous fluids. II. Thermal liquids
,”
J. Chem. Phys.
140
,
194507
(
2014
).
16.
S.
Mirigian
and
K. S.
Schweizer
, “
Elastically cooperative activated barrier hopping theory of relaxation in viscous fluids. I. General formulation and application to hard sphere fluids
,”
J. Chem. Phys.
140
,
194506
(
2014
).
17.
R. W.
Hall
and
P. G.
Wolynes
, “
Intermolecular forces and the glass transition
,”
J. Phys. Chem. B
112
,
301
312
(
2008
).
18.
K.
Koperwas
,
K.
Adrjanowicz
,
Z.
Wojnarowska
,
A.
Jedrzejowska
,
J.
Knapik
, and
M.
Paluch
, “
Glass-forming tendency of molecular liquids and the strength of the intermolecular attractions
,”
Sci. Rep.
6
,
36934
(
2016
).
19.
P. A.
Bonvallet
,
C. J.
Breitkreuz
,
Y. S.
Kim
,
E. M.
Todd
,
K.
Traynor
,
C. G.
Fry
,
M. D.
Ediger
, and
R. J.
Mcmahon
, “
Organic glass-forming materials: 1,3,5-tris(naphthyl)benzene derivatives
,”
J. Org. Chem.
72
,
10051
10057
(
2007
).
20.
C. M.
Whitaker
and
R. J.
McMahon
, “
Synthesis and characterization of organic materials with conveniently accessible supercooled liquid and glassy phases: Isomeric 1,3,5-tris(naphthyl)benzenes
,”
J. Phys. Chem.
100
,
1081
1090
(
1996
).
21.
T.
Komatsu
, “
Application of fragility concept to metallic glass formers
,”
J. Non-Cryst. Solids
185
,
199
202
(
1995
).
22.
P. K.
Gupta
and
J. C.
Mauro
, “
Composition dependence of glass transition temperature and fragility. I. A topological model incorporating temperature-dependent constraints
,”
J. Chem. Phys.
130
,
094503
(
2009
).
23.
S.
Martiello
,
D. R.
Cassar
,
E.
Alcobaça
, and
T.
Botari
, “
Machine learning unveils composition-property relationships in chalcogenide glasses
,” arXiv:2106.07749 (
2021
).
24.
Y.
Xia
,
B.
Yuan
,
O.
Gulbiten
,
B.
Aitken
, and
S.
Sen
, “
Kinetic and calorimetric fragility of chalcogenide glass-forming liquids: Role of shear vs enthalpy relaxation
,”
J. Phys. Chem. B
125
,
2754
2760
(
2021
).
25.
J. C.
Mauro
and
A. K.
Varshneya
, “
Multiscale modeling of arsenic selenide glass
,”
J. Non-Cryst. Solids
353
,
1226
1231
(
2007
).
26.
W.
Zhu
,
M.
Lockhart
,
B.
Aitken
, and
S.
Sen
, “
Dynamical rigidity transition in the viscoelastic properties of chalcogenide glass-forming liquids
,”
J. Non-Cryst. Solids
502
,
244
248
(
2018
).
27.
T.
Cosby
,
Z.
Vicars
,
M.
Heres
,
K.
Tsunashima
, and
J.
Sangoro
, “
Dynamic and structural evidence of mesoscopic aggregation in phosphonium ionic liquids
,”
J. Chem. Phys.
148
,
193815
(
2018
).
28.
T.
Cosby
,
U.
Kapoor
,
J. K.
Shah
, and
J.
Sangoro
, “
Mesoscale organization and dynamics in binary ionic liquid mixtures
,”
J. Phys. Chem. Lett.
10
,
6274
6280
(
2019
).
29.
W.
Xu
,
E. I.
Cooper
, and
C. A.
Angell
, “
Ionic liquids: Ion mobilities, glass temperatures, and fragilities
,”
J. Phys. Chem. B
107
,
6170
6178
(
2003
).
30.
V.
Meenakshisundaram
,
J.-H.
Hung
, and
D. S.
Simmons
, “
Design rules for glass formation from model molecules designed by a neural-network-biased genetic algorithm
,”
Soft Matter
15
,
7795
7808
(
2019
).
31.
R.
Böhmer
,
K. L.
Ngai
,
C. A.
Angell
, and
D. J.
Plazek
, “
Nonexponential relaxations in strong and fragile glass formers
,”
J. Chem. Phys.
99
,
4201
(
1993
).
32.
J. L.
Green
,
K.
Ito
,
K.
Xu
, and
C. A.
Angell
, “
Fragility in liquids and polymers: New, simple quantifications and interpretations
,”
J. Phys. Chem. B
103
,
3991
3996
(
1999
).
33.
D.
Huang
and
G. B.
McKenna
, “
New insights into the fragility dilemma in liquids
,”
J. Chem. Phys.
114
,
5621
(
2001
).
34.
R.
Richert
,
K.
Duvvuri
, and
L.-T.
Duong
, “
Dynamics of glass-forming liquids. VII. Dielectric relaxation of supercooled tris-naphthylbenzene, squalane, and decahydroisoquinoline
,”
J. Chem. Phys.
118
,
1828
(
2003
).
35.
G.
Ruocco
,
F.
Sciortino
,
F.
Zamponi
,
C.
De Michele
, and
T.
Scopigno
, “
Landscapes and fragilities
,”
J. Chem. Phys.
120
,
10666
10680
(
2004
).
36.
C.
Dalle-Ferrier
,
A.
Kisliuk
,
L.
Hong
,
G.
Carini
,
G.
Carini
,
G.
D’Angelo
,
C.
Alba-Simionesco
,
V. N.
Novikov
, and
A. P.
Sokolov
, “
Why many polymers are so fragile: A new perspective
,”
J. Chem. Phys.
145
,
154901
(
2016
).
37.
V. N.
Novikov
and
A. P.
Sokolov
, “
Poisson’s ratio and the fragility of glass-forming liquids
,”
Nature
431
,
961
963
(
2004
).
38.
K.
Kunal
,
C. G.
Robertson
,
S.
Pawlus
,
S. F.
Hahn
, and
A. P.
Sokolov
, “
Role of chemical structure in fragility of polymers: A qualitative picture
,”
Macromolecules
41
,
7232
7238
(
2008
).
39.
Q.
Qin
and
G. B.
McKenna
, “
Correlation between dynamic fragility and glass transition temperature for different classes of glass forming liquids
,”
J. Non-Cryst. Solids
352
,
2977
2985
(
2006
).
40.
J.
Krausser
,
A. E.
Lagogianni
,
K.
Samwer
, and
A.
Zaccone
, “
Disentangling interatomic repulsion and anharmonicity in the viscosity and fragility of glasses
,”
Phys. Rev. B
95
,
104203
(
2017
).
41.
A. K.
Gangopadhyay
,
C. E.
Pueblo
,
R.
Dai
,
M. L.
Johnson
,
R.
Ashcraft
,
D.
Van Hoesen
,
M.
Sellers
, and
K. F.
Kelton
, “
Correlation of the fragility of metallic liquids with the high temperature structure, volume, and cohesive energy
,”
J. Chem. Phys.
146
,
154506
(
2017
).
42.
F. H.
Stillinger
and
P. G.
Debenedetti
, “
Distinguishing vibrational and structural equilibration contributions to thermal expansion
,”
J. Phys. Chem. B
103
,
4052
4059
(
1999
).
43.
J.-H.
Hung
,
T. K.
Patra
, and
D. S.
Simmons
, “
Forecasting the experimental glass transition from short time relaxation data
,”
J. Non-Cryst. Solids
544
,
120205
(
2020
).
44.
S.
Yin
,
Z.
Shuai
, and
Y.
Wang
, “
A quantitative structure–property relationship study of the glass transition temperature of OLED materials
,”
J. Chem. Inf. Comput. Sci.
43
,
970
977
(
2003
).
45.
G.
Chen
,
Z.
Shen
,
A.
Iyer
,
U. F.
Ghumman
,
S.
Tang
,
J.
Bi
,
W.
Chen
, and
Y.
Li
, “
Machine-learning-assisted de novo design of organic molecules and polymers: Opportunities and challenges
,”
Polymers
12
,
163
(
2020
).
46.
S.
Takeda
,
T.
Hama
,
H.-H.
Hsu
,
T.
Yamane
,
K.
Masuda
,
V. A.
Piunova
,
D.
Zubarev
,
J.
Pitera
,
D. P.
Sanders
, and
D.
Nakano
, “
AI-driven inverse design system for organic molecules
,” arXiv:2001.09038 (
2020
).
47.
Y.
Zhang
and
X.
Xu
, “
Machine learning glass transition temperature of polymers
,”
Heliyon
6
,
e05055
(
2020
).
48.
S. F.
Swallen
,
K. L.
Kearns
,
M. K.
Mapes
,
Y. S.
Kim
,
R. J.
McMahon
,
M. D.
Ediger
,
T.
Wu
,
L.
Yu
, and
S.
Satija
, “
Organic glasses with exceptional thermodynamic and kinetic stability
,”
Science
315
,
353
357
(
2007
).
49.
A.
Sepúlveda
,
M.
Tylinski
,
A.
Guiseppi-Elie
,
R.
Richert
, and
M. D.
Ediger
, “
Role of fragility in the formation of highly stable organic glasses
,”
Phys. Rev. Lett.
113
,
045901
(
2014
).
50.
T.
Liu
,
K.
Cheng
,
E.
Salami-Ranjbaran
,
F.
Gao
,
C.
Li
,
X.
Tong
,
Y.-C.
Lin
,
Y.
Zhang
,
W.
Zhang
,
L.
Klinge
,
P. J.
Walsh
, and
Z.
Fakhraai
, “
The effect of chemical structure on the stability of physical vapor deposited glasses of 1,3,5-triarylbenzene
,”
J. Chem. Phys.
143
,
084506
(
2015
).
51.
M.
Tylinski
,
Y. Z.
Chua
,
M. S.
Beasley
,
C.
Schick
, and
M. D.
Ediger
, “
Vapor-deposited alcohol glasses reveal a wide range of kinetic stability
,”
J. Chem. Phys.
145
,
174506
(
2016
).
52.
A.
Laventure
,
A.
Gujral
,
O.
Lebel
,
C.
Pellerin
, and
M. D.
Ediger
, “
Influence of hydrogen bonding on the kinetic stability of vapor-deposited glasses of triazine derivatives
,”
J. Phys. Chem. B
121
,
2350
(
2017
).
53.
A. R.
Moore
,
G.
Huang
,
S.
Wolf
,
P. J.
Walsh
,
Z.
Fakhraai
, and
R. A.
Riggleman
, “
Effects of microstructure formation on the stability of vapor-deposited glasses
,”
Proc. Natl. Acad. Sci. U. S. A.
116
,
5937
5942
(
2019
).
54.
Y.
Chen
,
Z.
Chen
,
M.
Tylinski
,
M. D.
Ediger
, and
L.
Yu
, “
Effect of molecular size and hydrogen bonding on three surface-facilitated processes in molecular glasses: Surface diffusion, surface crystal growth, and formation of stable glasses by vapor deposition
,”
J. Chem. Phys.
150
,
024502
(
2019
).
55.
K. J.
Dawson
,
L.
Zhu
,
L.
Yu
, and
M. D.
Ediger
, “
Anisotropic structure and transformation kinetics of vapor-deposited indomethacin glasses
,”
J. Phys. Chem. B
115
,
455
463
(
2011
).
56.
S. S.
Dalal
,
D. M.
Walters
,
I.
Lyubimov
,
J. J.
de Pablo
, and
M. D.
Ediger
, “
Tunable molecular orientation and elevated thermal stability of vapor-deposited organic semiconductors
,”
Proc. Natl. Acad. Sci. U. S. A.
112
,
4227
(
2015
).
57.
T.
Liu
,
A. L.
Exarhos
,
E. C.
Alguire
,
F.
Gao
,
E.
Salami-ranjbaran
,
K.
Cheng
,
T.
Jia
,
J. E.
Subotnik
,
P. J.
Walsh
,
J. M.
Kikkawa
, and
Z.
Fakhraai
, “
Birefringent stable glass with predominantly isotropic molecular orientation
,”
Phys. Rev. Lett.
119
,
095502
(
2017
).
58.
Y.
Chen
,
M.
Zhu
,
A.
Laventure
,
O.
Lebel
,
M. D.
Ediger
, and
L.
Yu
, “
Influence of hydrogen bonding on the surface diffusion of molecular glasses: Comparison of three triazines influence of hydrogen bonding on the surface diffusion of molecular glasses: Comparison of three triazines
,”
J. Phys. Chem. B
121
,
7221
7227
(
2017
).
59.
Y.
Chen
,
W.
Zhang
, and
L.
Yu
, “
Hydrogen bonding slows down surface diffusion of molecular glasses
,”
J. Phys. Chem. B
120
,
8007
8015
(
2016
).
60.
S.
Samanta
,
G.
Huang
,
G.
Gao
,
Y.
Zhang
,
A.
Zhang
,
S.
Wolf
,
C. N.
Woods
,
Y.
Jin
,
P. J.
Walsh
, and
Z.
Fakhraai
, “
Exploring the importance of surface diffusion in stability of vapor-deposited organic glasses
,”
J. Phys. Chem. B
123
,
4108
4117
(
2019
).
61.
J. H.
Magill
and
D. J.
Plazek
, “
Physical properties of aromatic hydrocarbons. II. Solidification behavior of 1,3,5-tri-α-naphthylbenzene
,”
J. Chem. Phys.
46
,
3757
(
1967
).
62.
I.
Tsukushi
,
O.
Yamamuro
,
T.
Ohta
,
T.
Matsuo
,
H.
Nakano
, and
Y.
Shirota
,
J. Phys.: Condens. Matter
8
,
245
255
(
1996
).
63.
E. C.
Glor
and
Z.
Fakhraai
, “
Facilitation of interfacial dynamics in entangled polymer films
,”
J. Chem. Phys.
141
,
194505
(
2014
).
64.
S.-J.
Zou
,
Y.
Shen
,
F.-M.
Xie
,
J.-D.
Chen
,
Y.-Q.
Li
, and
J.-X.
Tang
, “
Recent advances in organic light-emitting diodes: Toward smart lighting and displays
,”
Mater. Chem. Front.
4
,
788
820
(
2020
).
65.
G. J.
Hedley
,
A.
Ruseckas
, and
I. D. W.
Samuel
, “
Light harvesting for organic photovoltaics
,”
Chem. Rev.
117
,
796
837
(
2017
).
66.
D.
Pires
,
J. L.
Hedrick
,
A.
De Silva
,
J.
Frommer
,
B.
Gotsmann
,
H.
Wolf
,
M.
Despont
,
U.
Duerig
, and
A. W.
Knoll
, “
Nanoscale three-dimensional patterning of molecular resists by scanning probes
,”
Science
328
,
732
736
(
2010
).
67.
J.
Gilbert
and
S.
Martin
,
Experimental Organic Chemistry
, 4th ed. (
Thomson Brooks/Cole
,
Belmont, CA
,
2006
), p.
708
.
68.
Y.
Zhang
,
E. C.
Glor
,
M.
Li
,
T.
Liu
,
K.
Wahid
,
W.
Zhang
,
R. A.
Riggleman
, and
Z.
Fakhraai
, “
Long-range correlated dynamics in ultra-thin molecular glass films
,”
J. Chem. Phys.
145
,
114502
(
2016
).
69.
T.
Lan
and
J. M.
Torkelson
, “
Fragility-confinement effects: Apparent universality as a function of scaled thickness in films of freely deposited, linear polymer and its absence in densely grafted brushes
,”
Macromolecules
49
,
1331
1343
(
2016
).
70.
J. E.
Pye
and
C. B.
Roth
, “
Physical aging of polymer films quenched and measured free-standing via ellipsometry: Controlling stress imparted by thermal expansion mismatch between film and support
,”
Macromolecules
46
,
9455
9463
(
2013
).
71.
A.
Rohatgi
, Webplotdigitizer, copyright 2010–2021, https://apps.automeris.io/wpd/.
72.
K.
Dawson
,
L.
Zhu
,
L. A.
Kopff
,
R. J.
McMahon
,
L.
Yu
, and
M. D.
Ediger
, “
Highly stable vapor-deposited glasses of four tris-naphthylbenzene isomers
,”
J. Phys. Chem. Lett.
2
,
2683
2687
(
2011
).
73.
A.
Döß
,
M.
Paluch
,
H.
Sillescu
, and
G.
Hinze
, “
From strong to fragile glass formers: Secondary relaxation in polyalcohols
,”
Phys. Rev. Lett.
88
,
095701
(
2002
).
74.
D.
Heczko
,
K.
Jurkiewicz
,
M.
Tarnacka
,
J.
Grelska
,
R.
Wrzalik
,
K.
Kamiński
,
M.
Paluch
, and
E.
Kamińska
, “
The impact of chemical structure on the formation of the medium-range order and dynamical properties of selected antifungal APIs
,”
Phys. Chem. Chem. Phys.
22
,
28202
28212
(
2020
).
75.
K.
Kawakami
, “
Ultraslow cooling for the stabilization of pharmaceutical glasses
,”
J. Phys. Chem. B
123
,
4996
5003
(
2019
).
76.
L.-M.
Martinez
and
C. A.
Angell
, “
A thermodynamic connection to the fragility of glass-forming liquids
,”
Nature
410
,
663
667
(
2001
).
77.
R. H.
Higgins
, “
A simple correlation of molecular weights and refractive indices
,”
J. Elisha Mitchell Sci. Soc.
110
,
39
45
(
1994
).
78.
C. J. F.
Böttcher
and
P.
Bordewijk
,
Theory of Electric Polarization
(
Elsevier Science Limited
,
1978
), Vol. 2.
79.
D. W.
Brown
and
L. A.
Wall
, “
Glass transition temperatures of several fluorine-containing polymers
,”
J. Polym. Sci., Part A-2
7
,
601
608
(
1969
).
80.
M.
Rowe
,
G. H.
Teo
,
J.
Horne
,
O.
Al-Khayat
,
C.
Neto
, and
S. C.
Thickett
, “
High glass transition temperature fluoropolymers for hydrophobic surface coatings via RAFT copolymerization
,”
Aust. J. Chem.
69
,
725
734
(
2016
).
81.
C.
Fetsch
and
R.
Luxenhofer
, “
Thermal properties of aliphatic polypeptoids
,”
Polymers
5
,
112
127
(
2013
).
82.
D. J.
Allen
and
H.
Ishida
, “
Physical and mechanical properties of flexible polybenzoxazine resins: Effect of aliphatic diamine chain length
,”
J. Appl. Polym. Sci.
101
,
2798
2809
(
2006
).
83.
M.
Soccio
,
N.
Lotti
,
L.
Finelli
,
M.
Gazzano
, and
A.
Munari
, “
Aliphatic poly(propylene dicarboxylate)s: Effect of chain length on thermal properties and crystallization kinetics
,”
Polymer
48
,
3125
3136
(
2007
).
84.
K.
Kempe
,
E. F.-J.
Rettler
,
R. M.
Paulus
,
A.
Kuse
,
R.
Hoogenboom
, and
U. S.
Schubert
, “
A systematic investigation of the effect of side chain branching on the glass transition temperature and mechanical properties of aliphatic (co-)poly(2-oxazoline)s
,”
Polymer
54
,
2036
2042
(
2013
).
85.
H. A.
Schneider
, “
Polymer class specificity of the glass temperature
,”
Polymer
46
,
2230
2237
(
2005
).
86.
N.
Soszka
,
B.
Hachuła
,
M.
Tarnacka
,
E.
Ozimina-Kamińska
,
J.
Grelska
,
K.
Jurkiewicz
,
M.
Geppert-Rybczynska
,
R.
Wrzalik
,
K. A.
Grzybowska
,
S.
Pawlus
 et al., “
The impact of the length of alkyl chain on the behavior of benzyl alcohol homologous. The interplay between dispersive and hydrogen bond interactions
,”
Phys. Chem. Chem. Phys.
23
,
23796
(
2021
).
87.
Penn glass database, https://glass.apps.sas.upenn.edu.

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