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Spectral characteristics of several series of more unusual aromatic hydrocarbons
JOURNAL OF MOLECULAR SPECTROSCOPY6, 181-198 (1960)
Spectral
Characteristics
More
Unusual E.
Znstitde
of Several
Aromatic MILLER
Series
of
Hydrocarbons*
LAYTON.
JR.
for Atomic Research and Department of Chemistry, State Universitg, ilmes, Iowa
Zowa
Energy and intensity data are presented for T-electronic transitions in several families of more unusual aromatic hydrocarbons. Emphasis is placed on certain special classes of benzene and naphthalene compounds, systems of nuclei connected by polyene chains and compounds containing five- and sevenmembered rings. I. INTROI~UCTION
This
collection
energies
a nonalternant8 rather
sociated to the
of transitions have
and l’latt
empirical
(1,
analogies with
of the kilo-Kayser transitions structure
been
based
(1 kK
equals
have
the use of a correction
for solut’ion
and Ruedenberg
1 kli
tions while tions
no change
originate
ground
respectively),
upper
transitions
state.
Some
data.
(‘il
only
* Contribution No. 735. Work was performed Energy Commission. 181
but
given
values
J’ollowing
geometry.
thus any vibraof a some-
assumption
predicates
the procedure of the strong
‘L transitions.
and Mulliken-
by the label
on another
in the Ames Laboratory
of Ham ‘B transi-
Since all transi-
and N in the Platt
as shoulders
in
to correspond
internuclear
are identified
as-
are given
and intensity first
by
(3) , along with
restriction;
to the energy
the transitions appear
The
of
mole-
and the fine structure energy
a static
for the weak state
of aromatic
and are chosen
with
measured.
spectral
has been made
C2oulson notations,
The
and the wavelength
has been added
in a common
intensities,
is chosen by the latter been
on those
to be exhaustive,
types
and Ruedenberg
1000 cm-‘)
molecule
transition
an emphasis
the aid of the considerations
transitions.
has been smoothed maximum
to different
by Ham
on wavelengths, electronic
maximum
(Y),
with
of electronic
with
is not, meant
peculiar
made
of an isolated
‘l’he I’ranck-Condon rional
compounds,
21, as amended
part,icular
what, artificial
as a compilation
of aromatic
nat,ure. As such, the collection
hssignments
Elevens
is presented
groups
representative
cules.
units
of data
for several
band.
of the These
of the U. S. Atomic
are accordingly marked ( sh. ). E signifies the energy corresponding t,o the wavelength of the intensity maximum. Xlthough care has been taken in the assignment of these transitions, an element of caution is necessary since the assignments have been basically of an empirical nature and not actually based on quantit,ative calculations for rigorous models. I’lntt (a, 4 ) has definitively established separate intuitive models for condensed aromatic and extended polyene systems. Intermediate type molecules, such as stilbene (So. 12) or cinnnmylidene indene (Ko. 91 ), present thenot unusual problem of possessing distinct features not readily interpreted by either model. A comprehensive theory of classification for all aromatic systems should he applicable to such intermediate cases, but the concept of a G or H band in a condenred system, or an /, band in a polyene, can be ambiguous or even misleading. In :I strict sense, our use of the l’latt nomenclature is only meaningful for the COILdensed ring systems, the exception being the extent, to which a correspondence to Mulliken-Coulson and Clar nomenclature is valid. (See papers by T
on page 198.)
I
P.
(4)
(2)
spectrum
Ref.:
(5) BP=
135
collected
(3) P.
Tetraphenylmethaneo
Ref.:
76
$
I
a
the
c
36
16
Q
4
at
154
.@Ha
112
(2) spectrum
(3)
fig.
8
fig.
164,
(1) p.
Trlphenylmethane
~ef.:
Diphenylmethane
l~eferencca
5.
4.
3.
158,
148
(2) spectrum
(1) p.
~ef.:
p.
(1)
Mel*.:
1. Benzene
PHENYL POLYANES
end
of
2.04
7.
per.:
(3) P.
Phenyletbane
this
lLb
lLa
report.
52.9
lBb
4.86
I 4.87
E 54.5
lBa
a.
%I
T
(8) (9)
2.44
38.4
lLa
(2)
Ref.:
p.
164,
(8)
(7)
(6)
(3) P. 76
(1)
76
spectrum
1,2-Dlphenylethane (bibcnzyl)
Ref.:
1,l:Dlphenylethane
(7)
4.72 3.88
54.2 48.6
lBa,b
6)
39.4
l%
3.e2
6.
I
49.5
IL,
4.66
Intensity (108 E ma.&)
E
55.4
l%,b
T
Energy
Transition
fig.
113
36
“OCH3
T
T
1..
'Lb
lLa
lBa ,b
I
5.00 4.28 2.58
46.8 37.5
I
3.89
2.23
53.6
E
I
(ah.)
--I-37.9
k0.3
I
4.76
E
53.9
cu
R
185
34.-36.
26~33.
25.
(10)
pp.
(3)
serial
P.
p.
242,3
265
243,4
no.
(13) P. 265
(5)
(3)
La transition
Ref.:
1
Q-Polyphenyls
(i3)
(5)
p.
1La transitxon
Ref.: (3)
171
fig.
242-245
spectrum
(2)
166,
p.
(1)
m-Polyphenyls
Ref.:
p-Terphenyl
491
a4
36.
35.
34.
25.
33.
32.
t
I
14
13
12
11
30.
31.
5
10
29.
a
27.
28.
7
26.
’
”
?--I-
lLa
lBb
lBa
T
t
I
39.3
35.4
39.5
39.5
35.5
35.5
39.5
35.5
t
36.3
4.75
4.80
4.59
4.40
I
5.51
5.49
5.45
5.40
5.37
5.33
5.33
5.26
4.52
50.4
E
4.99 4.90
57.7
I
E
v
41.
40.
39.
38.
37.
P. 281
(2)
spectrum
250
(2)
spectrum
Fief.:
(2)
spectrum
1,6-Dlphenyln30hthalene
Ref.:
300
277
2-Benzylnaphthalene
% Ref.: (2) BpeCtlwm 297
2-Phenylnaphthalene
Ref.:
l-Phenylnaphthalenc
(3)
195
167. fig. 47
(2) spectrum
Ref.: (1) P.
Nsphthalene
NAPHTHALENES
lLa
T
35.0
E
4.05
I
‘G \I
44.
43.
42.
(20)
(10)
(20)
(10)
(3)
(2)
Ref.:
(20)
(10)
(3)
(2)
281
serial
281
spectrum
serial
P.
spectrum
P.
2,2-Dlnaphthyl
Ref.:
serial
%
(3)
281
spectrum
P.
(2)
1,2-Dlnaphthyl
Ref.:
1, I-Dinaphthyl
no.
309
no.
306
n0.
303
260
259
258
T
lLb
E
?
I
3.45
31.8
P
4.15
34.6
I 4.58
E 45.1
(sh.)
(sh.)
lLb
lL.4
‘Bb
IBa
4.20
32.8
3.18
4.99
40.4
30.0
4.62
48.1
48.
47.
46.
45.
Ref.:
Ref.:
P.
501,
501,502
p.
#c
502
Cs Ref.:
Q
(23)
(21)
p.
c=C+=c 501,502
_G
TetrephenJlParlldiphenylquinodiocthane (Tchlchlbablnc’a hydrocarbon)
(22)
(21)
(22)
(21)
=
Tetraphenylparabenzylquinodimethane
BENZENE QUINONOIDS
--t--l-
t-t
ILa
IBb
T
VI
t-t-
l%
T
tt-
lLa
lBb
T E
17.4
E
24.0
37.5
I
4.91
I
4.58
4.14
& 30
Ref.: (26)
(25)
~ef.: (24) p. 279
VII BIPHENYLENES
Ref.: (21) p. 501,502
T ‘19. Tetraph~nylpar~~tllb~~yl~uinodi~~th~~~
VIII
54.
(28)
(21) P. 499
(27)
(21) p. 499
Ref.: (10) serial no. 510
( ~g~g-Bifl"orenyl
Diblphcnylene-ethylene
DIPHENYLENE POLYENBS
-t-t-
21.8
30.8
"b lLe
E 42.0
T lBa
I
I
I
4.37
4.63
4.09
& *
60.
59.
57.
(27)
(24)
P. 276
aerial
(10)
(11)
spectrum
(2)
164,
~cf.: (1)
15
nos.
311
fig.
H2
go
37
L 401
h p.
aromatic
~OLI. 52 & 53
fig.
a cyclic
60
P.
with
158.
serial
p.
FlUOrene
Analogy
(10)
Ref.: (1)
Ref.:
a+ai=c
Blphenylcne-1-dlphenyl-4,4-butadiene
151
T
system
% lCb?
I%
would
‘La
la,
%3
T
E
‘El a(~
4.56
33.8
38.2
44.0
4.70
49.2
I 60.5
n-label
4.63
4.53
38.5 25.8
I 4.G
E 42.0
I% ha
T 1 'ia
lLh
!-
I
T---l23.:*
hb
lL3 1. a
lBb
4.22
32.2
27.5
40.7 Tl)I1 >J1 >I, fib B, La Lb 30.7
4.22
4.21 :slr.)
4O.L 0
4.70
I
3.s
IL,
44.3
E
2.2.4
4.31'
'I.?5 3;.c 31.'_S
4.rc1 47.3
I
4.21 3.07
29.1
:-
4 .'j6
j2.s
4.48
3Y.l
45.0
bt
Ia3
llt, l---r
-t-t
lLa
I%
lBd
I
$ C
69.
68.
67.
(30)
(2) spectrum
538 ‘;
1 28.0
(
3.37
(31)
(2)
spectrum
(2)
(32)
spectrum
xef.:
Ref.:
(31)
(2)
(31)
(2)
spectrum
spectrum
g-phenyl-1,2,5,6-dlbenz
ike.:
g-Phenylfluorene
Ref.:
&
536
535
318
534
q-s+
“““-D~b~~~~fl~~~~ .q$Jg
rter.:
74.
72.
71.
(33)
(2)
(31)
(2)
spec:
spectrum
Ref.:
(38)
(36)
(34)
(37) Acepleladylene
Ref.:
Rubicene
Ref.:
5
!,-phenyl-1,2,3,4,7,8-tribenzofluorene
-t-i-
lLa
l4
“b
T
I----I-
lLa
lLb
lab
”
4.61 3.7: 4.04
34.5 2-.O 20.4
I
4.20 23.6
F
4.69
35.1
I 4.83
E 40.6
*
assignment
17.
Raf.:
(41)
(49)
(2)
spectrum
that
234
.i.cce?tly,
56
the
three
(3’0,
P
30.5
ILb
44.5 37.7
.‘J
E
levels
(36)
% ~
:
Filllams
acepleiadiene
2.41
4.68
4.70
4.94
I
4.7
I
have
3.58
3.34
4.72
I
parallel
reported
Ham and
has
of
who assigned
calculations
lowest
1_
3.
the
26.4
30.2
1L 1 1. %
37.;
1,-b
iI 42.5
‘“.’
Y
-a
1,
l_ -i
Sidman
and
3f
however,
that
472
rig.
analogously,
follows
324
indlcdtl’lg
Acenaphthylene
p01ari.Zati0ns.
r~as’1~eme”ts
‘25)
dccpleiadyiene
Cur
?.ue~j~lh?r~.
-in,:
(34)
6.
SFectrum
(2)
(24)
p.
167,
~c]nce~a~hthylew
(1)
Pyrene’
76.
3cf.:
Cyclohepta
7c.
81.
80.
79.
7s.
(42)
(2)
(40)
p.
(24)
p.
403
Rer.:
(24)
p.
405
3,4-Benzfluoranthene
~ef.:
3-9
spectrum
(2) (24)
p.
(1)
168,
spectrum
2,3-Benzfluxanthene
Ref.:
Flluoranthene
~ef.:
Perinaphthene
235
Ci!$
435
fig.
a
51
H2
E
I
I
2P.f 27.1
lit
34.2
40.1
3.E
4.00
4.55
‘1.57
3.52
23.4
E
3.70
3.91
4.86
I
3.>3
4.53
4.58
4.50
28.0
33.5
40.1
IL,
lBb
lBa
lLa
lLD
%
1Ba
T
lLa
1%
lBb
%
?--lT
T
XI
(43)
(24)
(2)
p.
407
spectrum
Ref.:
(43)
(24)
(2)
P.
H-C-H
408
spectrum
11,12_Benzfluoranthene
Ref.:
lO,ll-Bcnrfluor~nthcnt
FULVENES
83.
82.
543
-I-
lLa xl I% 25.5 33.8 42.5
I
168,
fig.
CI
2.47
2.90
4.23
4.58
90.
89.
(47)
(27)
(27)
(27)
Ref.: (1)
p.
168,
Dlphcnyldibcnzofulvene (Banrhydry lldencE;b
Ref.:
.
52
do fig.
Phcnyldibcnzofulvene (Benzylldene fluorene)
Ref.:
T
E
lLb
4.03 3.98 2.94
36.6
29.6
4.86 44.4
53.6
7-t ‘La
“b
lR.
I
4.14
4.10 HC
I
2.48
3.98
Phcnylbenzofulvene (Benzylldenc lndcnc)
52
4.09
08.
(46)
p.
4.70
4.79
I
(27)
(1)
I
4.33
Ref.:
-&D
4.09
c
4.06
~
4.19
Dlphinylfulvene
(46)
4.14
87.
ref.:
Phenylfulvene
4.50
4.70
86.
(sh.)
(ah.)
193
102.
l
(53)
(49)
(11)
(52)
Indcno-azulene
Ref.:
6-Phenylazulcnc
Ref.:
P-Phenylazulenc
0
This
state
Ref.:
1s
(55)
(541
doubly
degenerate,
0..:.,
..’
CYCLOHEPTATRIENYLIUM ION (Tropyllum ion)
behavlour.
XIII
101.
100.
99.
it
will
have
I
but
? 36.4
1
T IL’
intensity
I
I
I 3.64
I
L,
‘7J-fg-y ‘j-zig
XIV
10-r.
106.
105.
104.
(56)
157)
(57)
a
(57)
Bef.:
(58)
(57)
(2)
spectrum
Trlphenylethylene
Ref.:
Cycloheptadlene-2.6
Benzylldene-l-dibenzo-2,3,6,7
Ref.:
8
156
ir-%
c
H2C
H\
Benzylidene-1-dlbenzo~2,3,6,7 cycloheptatriene-2.4.6
Ref.:
#ethylene-1-dibenko-2,3,6, cycloheptatrlene-2,4,6
~ef.: 46
=1;:
-CYCLOHEPTAPOLYENES,-FULVALENES, & -HEPTAFULVALENES
Dlbenlo-2,3,6,7 Cycloheptatrlene-2,4.
DIBENZO 103.
SPECTRAL
CHARACTERISTICS
OF HYDROCARBONS
195
108.
~ef.:
spectrum
(2)
160
(58) (59) (60) 54.
109.
Dlbiphenylene-ethylene
See Section VIII
Fluorcnylbenzylidcne-1-dibenzo-2,3,6,7 Cyclohcptstrlene-2,4,6
Ref.
:
(21)
p.
500
(61)
110.
Tctrabenzo-2,3,6.7,2’,3’,6’,7’ Heptarulvalene
REFERENCES 1.
2. 8.
4. 6. 6.
7. 8. 9. 10.
T
FOR
E
lBa
46.5
l%
34.5
SPECTRAL
DATA
of Vacuum Ultraviolet Spectra of Oryanic Compounds in Solution, H. B. Klevens and J. R. Platt, reprinted from Technical Report (1953-195X, Part I, Laboratory of Molecular Structure and Spectra Dept. of Physics, University of Chicago. R. A. FRIEDEL AND M. ORCHIN, “Ultraviolet Spectra of Aromatic Compounds,” Wiley, New York, 1951. A. E. GILLAM AND E. S. STERN, “Introduction to Electronic Absorption Spectroscopy in Organic Chemistry.” Edward Arnold, London, 1958. M. R.AMART-LCCAS AND M. J. HOCH, Bull. Sot. Chim. France 2, 1376 (1935). A. E. GILLAM AND D. H. HEY, J. Chef?l. Sot. p. 1170 (1939). M. RAMART-LUCAS, Bull. Sot. Chim. France 61, 289 and 965 (1932). M. RAMART-LUCAS, Bull. Sot. Chim. France 10, 13 (1943). A. HILMER AND E. PAESCH, 2. Physik. Chem. 161, 46 (1932). J. R. PLATT AND H. B. KLEVENS, Chem. Reus. 41, 301 (1947). American Petroleum Institute Research Project 44. National Bureau of Standards. Catalog of IJltraviolet Spectral Datta.
Survey
11. H. B. KLE\.ENiS, J. (‘hew. Ph!/s. 18, l(ifX3 (1950) f2. A. SMAK~-L.\ AXI> A. W.ISHERBI.\N. %. Physik. C’ht~m. Al& 353 r1931). 13. (:. W. WHEIASI,, “ Iteson:tnw in ()rg:rnic Chemintr~.” Wiley, Sew Yorli, 1953. 14. K. W. HAI-SSER, W. ~
I’:tris.
1952.
22. ,4. 1’1-I~Ix.4N. B. PI.LI,x4s, AND Y. HIRSHBERG.
I<. I). I
null.
Sw.
C’h.im.
9.S. W. THEII.AC.KER AND W. OZEGOMYKI,
,?4. b:. CLAR,
“iirom:ttixhe
Frcrtw
p. 707
I<. FISCHER,
I). (;ISSRI.RG
(1051).
Hrr. 73, 899 (19401.
Iiotllenw:ts:i~r,to~~.”
Springer,
Hrrlin, 1952. SW. 63, 3230 (1941). 77, 6022 (1855).
25. E. 1’. C.~RR, I,. W. ~‘ICKETT. ASD 1). \:ORIS, J. Lt)n. I’hetu.
26. &I. I’. cliv\ ASD J. F. &lY’KER. J. .tr,!. (‘hem. SW. 27. E. 1). BER(;MAXS AND Y. HIRSHBERG, Htr//. SOC. C’hirri. Frurlw p. 1091 (1950). 28. R. KUHN AND A. WINTERSTEIX, Hell,. (‘him. .-lr,ta 11, 116 (1925). 29. W. ZIEGENBEIN ASI) W. TRERS, ;lr~r~. 696, 211 (1955). SO. W. V. MAYXEORLI ANI) E. 11. F. ROE:, Proc. Ko!g. Sot. A162, 299 (1935). 31. It. D;. JOSES, J. .l~r. Chem. Ser. 67, 2021 (1945). 32. (:. I<. BRADSHER hS1) I,. J. WISSCW. .I. .t,tf.C’hrm. SOC. 68, 2149 (1946). 33. R. ?;. JONES. (‘hem. Rc~s. 41, 353 (1947). 34. J. W. SIDMAS, .I. .lnl. C’hrtu. SOC. 78, 4217 (1956). 55. iY. S. H.~M ANI) K. RI.EI)ESBERG, J. (‘Kerry. Ph!/s. 26, 13 (1956). 36. R. WII.I,IAIVI~, J. Ch,em. Phys. 26, 1186 (1957). 37. V. BOEKELHEIDE, W. E. T,an-w.~~s~~, AXI) C.-T. L1r1, J. ;lw. (‘hem. Sot. 73, 2432 (1951). 38. I>. S. MCCLCRE, Solitl St&e Phys. 8, 27 (1959). 39. 1). H. REID, W. H. STAFFORD, AsI) J. 1’. W.4RIJ, J. (‘her/r. SOC’. 11. 1193 (19553. 40. A. 1’~LLD~AN, B. PULLMAN, E. 1). RERGMA~N. c:. BERTHIER, E. FI%‘HER. \i. HIRSHBERG, AND J. I'ONTIS, J. chin!. phys. 48, 359 (1951). 41. I,. C. CRAIG, W. A. JAUJBS, ANI) (+. I. LAVIS. J. Niol. (‘hem. 139, 277 (1941). 42. V. BOEKELHEIDE ANI) c. K. LARRABEE, J. ilrrr. ChenI. Sot. 72, 1245 (1950). 43. 31. ORCHIK, I,. REGGEI,, R. A. FRIEDEI,, ASI) E;. 0. WOOLFOIX, T’. S. RIG. Miraes Tech. Paper 708, 19 (1948).
44. 0. 45. J.
KRUBER
AND (+. (+RIGOLEIT,
THIEC AND J. WIEMANN,
Krc. 87, 1895 (1954).
R~tll. Sot.
46. J. H. I)AY AND J. c’. I,osiuax.
(‘him. Frtrnc? 11, li7
Ohio J. Science
(1956).
62, 335 (1952).
(Ordinntes :u-e rrroneousl~ In\)elled IOF I/I,, ; should he log 1(,/f .J 47. R. A. MORTOS AND A. J. A. (;OUVEIA. J. f’her)~. Sot. p. 911 (1934). 48. I). IS. MANN, J. Ii. PLATT. AND H. B. ELEVENS, J. C’hem. Phys. 17, 481 (1949). 49. P. A. PLATTNER 50. P. A. PLATTNER, 51. J. R. ?;VNN
AND E. HEILBRONNER,
AND W. S. RAPSON,
52. E. 1). BERCMANN 55. I’. A. PLATTSER,
Helrl. (‘hinl.
A. FI~RsT, AND W. KELLER, AND R. IKAN,
J. C’hea~. Sot.
ilrta
Hell). C’him.
31, 804 (19483. Acte
32, 2464 (1949).
11. 825 (1949).
.I. .~NI. Chw~. Sot. 78, 1482 (1956).
A. FI-RST, AI. (+OHUON. AND I<. ZIMMERMAN,
(1950). 54. W. vex E. I~OERING ANI) I,. H. Iisos,
.J. .lm.
C’hrm.
Sot.
Helu. C’him.
76, 3203 (1951).
.4cta
33,
1910
SPECTRAL
CHBRACTERISTICH
OF HYDROCARBONS
1!>7
55. J. N. MCRRELL AND H. C. LONGUET-HIGGINS,J. Chen~.Phus. 23, 2317 (1955). 66. T. W. CAMPBELL,R. GINSIG, AND H. SCHMID.Helv. Chim. dcta 36, 1193 (1953). 57. E. D. BERGMANN,E. FISCHER,11. ~+IKSBI.RG,Y. HIRSHBERG,D. LAVIE, M. MAYOT, A. PULLMAN, A&D B. P~I,LRIAN,HlrZZ.Sot. Chinl. France p. 6% (1951). 58. B. ARENDS, Ber. 64, 1936 (1931). 59. E:. II. BERGMANX,II. GINSBVRG, Y. HIRSHBERG,M. MAYOT, A. PULLMAN,AND B. Pmr,MAX, Hull. Sot. Chim. France p. 697 (1951). 60. H. LEY AXD F. RINKE, Ber. 66, 771 (1923). 61. B. PVUMAX. A. PGLLMAN,E. D. BERGMAKN,H. BERTHOD,E. FISCHER,Y. HIRSHBERG. I). L;IVIE, BND hf. MAYOT, Bull. sec. Chim. France p. 73 (1952).
TABLE
I
EMPIRICALFEATURES OF AROMATICSPECTRALTRANSITIONS
1,4\iTt )S
198
have not utilized an exact model but have assumed that all of our systems were amenable to a naive theoretical treatment and, accordingly, have utilized the simple Watt notation, which arises from the perimeter model of condensed aromatic hydrocarbon ring systems. Table I gives spectral features peculiar to vapor phase transitions in catncondensed sis-membered aromatic ring systems, with equivalent) symbols of the various schools indicated. Most of these generalizations were originally noted hy Klevens and I’latt ( 1,B ) . Many of I’lstt’s ‘C”hands have more recently been reinterpreted as ‘R hands. Since ‘C’ transitions are of a quadrupole nature, however, intensity features should lie between the ‘B and ‘L values. The given numerical ranges for the ‘C hands should be considered as tentative. These characteristics can he helpful, with judicious discretion, in classifying bands, but the visualization of approximate molecular symmetry wave functions and Hund’s rules may give a more consistent systematization, especially when accompanied by the intensity information obtainable from the use of transition moments. Icor a more quantitative interpretation of some of the molecules considered herein and many of the more common varieties, profitable use can he made of the tahulations of eigenvalues and eigenvectors given by Coulson and Daudet (8) und by Ham and Ruedenberg (9). The present collection of spectral data was undertaken, following a suggestion by Dr. Ii. Ruedenberg, in conjunct,ion with a theoretical invest,igation of the spectra of a large numher of hydrocarbons by R. Hummel and K. Ruedenberg. RECEIVED:
March
28, 1959. TEXT
1. 2. 3. 4. 5. 6. 7. 8.
9.
R.EFEREKCES
H. B. ELEVENS AXD J.R. ~'I,ATT,J. Chen~. Phys. 17,470 (1949). J. R. PLATT, J. Chem. Phys. 17,484 (1949). N. 8. HAM ANI) K. RUEDEKBERG, J. Chum. Phys. 26, 13 (1956). J. R. PLATT, in “Radiation Biology,” A. Hollaender, ed., Vol. III, Chapter 2. pp. 71-123 McGraw-Hill, New York, 1956. M. J. S. DEWAR AND H. C. LONGKET-HIGGINS, Proc. Phys. Sot. A67, 795 (1954). H. C. LONG~JET-HIGGINS,Aduanres in Chem. Phys. 1, 239-265 (1958). B. I'TLLMAN AND A. PULI.MAN, “Les Theories Electroniques de la Chimie Organiqne.” Masson et Cie., Paris, 1952. C. A. C~ULSON AND R. I~AUDEL, eds., “Dictionary of Values of Molecular Constants.” Vols. I, II, III. Mathematical Institute, Oxford, and the Centre dechimie Thkorique de France, Paris, 1959. N. S. HAM AND Ii. RUEDEKBERG, 1. Chew. Phys. 29, 1199 (1958).
Spectral
Characteristics
More
Unusual E.
Znstitde
of Several
Aromatic MILLER
Series
of
Hydrocarbons*
LAYTON.
JR.
for Atomic Research and Department of Chemistry, State Universitg, ilmes, Iowa
Zowa
Energy and intensity data are presented for T-electronic transitions in several families of more unusual aromatic hydrocarbons. Emphasis is placed on certain special classes of benzene and naphthalene compounds, systems of nuclei connected by polyene chains and compounds containing five- and sevenmembered rings. I. INTROI~UCTION
This
collection
energies
a nonalternant8 rather
sociated to the
of transitions have
and l’latt
empirical
(1,
analogies with
of the kilo-Kayser transitions structure
been
based
(1 kK
equals
have
the use of a correction
for solut’ion
and Ruedenberg
1 kli
tions while tions
no change
originate
ground
respectively),
upper
transitions
state.
Some
data.
(‘il
only
* Contribution No. 735. Work was performed Energy Commission. 181
but
given
values
J’ollowing
geometry.
thus any vibraof a some-
assumption
predicates
the procedure of the strong
‘L transitions.
and Mulliken-
by the label
on another
in the Ames Laboratory
of Ham ‘B transi-
Since all transi-
and N in the Platt
as shoulders
in
to correspond
internuclear
are identified
as-
are given
and intensity first
by
(3) , along with
restriction;
to the energy
the transitions appear
The
of
mole-
and the fine structure energy
a static
for the weak state
of aromatic
and are chosen
with
measured.
spectral
has been made
C2oulson notations,
The
and the wavelength
has been added
in a common
intensities,
is chosen by the latter been
on those
to be exhaustive,
types
and Ruedenberg
1000 cm-‘)
molecule
transition
an emphasis
the aid of the considerations
transitions.
has been smoothed maximum
to different
by Ham
on wavelengths, electronic
maximum
(Y),
with
of electronic
with
is not, meant
peculiar
made
of an isolated
‘l’he I’ranck-Condon rional
compounds,
21, as amended
part,icular
what, artificial
as a compilation
of aromatic
nat,ure. As such, the collection
hssignments
Elevens
is presented
groups
representative
cules.
units
of data
for several
band.
of the These
of the U. S. Atomic
are accordingly marked ( sh. ). E signifies the energy corresponding t,o the wavelength of the intensity maximum. Xlthough care has been taken in the assignment of these transitions, an element of caution is necessary since the assignments have been basically of an empirical nature and not actually based on quantit,ative calculations for rigorous models. I’lntt (a, 4 ) has definitively established separate intuitive models for condensed aromatic and extended polyene systems. Intermediate type molecules, such as stilbene (So. 12) or cinnnmylidene indene (Ko. 91 ), present thenot unusual problem of possessing distinct features not readily interpreted by either model. A comprehensive theory of classification for all aromatic systems should he applicable to such intermediate cases, but the concept of a G or H band in a condenred system, or an /, band in a polyene, can be ambiguous or even misleading. In :I strict sense, our use of the l’latt nomenclature is only meaningful for the COILdensed ring systems, the exception being the extent, to which a correspondence to Mulliken-Coulson and Clar nomenclature is valid. (See papers by T
on page 198.)
I
P.
(4)
(2)
spectrum
Ref.:
(5) BP=
135
collected
(3) P.
Tetraphenylmethaneo
Ref.:
76
$
I
a
the
c
36
16
Q
4
at
154
.@Ha
112
(2) spectrum
(3)
fig.
8
fig.
164,
(1) p.
Trlphenylmethane
~ef.:
Diphenylmethane
l~eferencca
5.
4.
3.
158,
148
(2) spectrum
(1) p.
~ef.:
p.
(1)
Mel*.:
1. Benzene
PHENYL POLYANES
end
of
2.04
7.
per.:
(3) P.
Phenyletbane
this
lLb
lLa
report.
52.9
lBb
4.86
I 4.87
E 54.5
lBa
a.
%I
T
(8) (9)
2.44
38.4
lLa
(2)
Ref.:
p.
164,
(8)
(7)
(6)
(3) P. 76
(1)
76
spectrum
1,2-Dlphenylethane (bibcnzyl)
Ref.:
1,l:Dlphenylethane
(7)
4.72 3.88
54.2 48.6
lBa,b
6)
39.4
l%
3.e2
6.
I
49.5
IL,
4.66
Intensity (108 E ma.&)
E
55.4
l%,b
T
Energy
Transition
fig.
113
36
“OCH3
T
T
1..
'Lb
lLa
lBa ,b
I
5.00 4.28 2.58
46.8 37.5
I
3.89
2.23
53.6
E
I
(ah.)
--I-37.9
k0.3
I
4.76
E
53.9
cu
R
185
34.-36.
26~33.
25.
(10)
pp.
(3)
serial
P.
p.
242,3
265
243,4
no.
(13) P. 265
(5)
(3)
La transition
Ref.:
1
Q-Polyphenyls
(i3)
(5)
p.
1La transitxon
Ref.: (3)
171
fig.
242-245
spectrum
(2)
166,
p.
(1)
m-Polyphenyls
Ref.:
p-Terphenyl
491
a4
36.
35.
34.
25.
33.
32.
t
I
14
13
12
11
30.
31.
5
10
29.
a
27.
28.
7
26.
’
”
?--I-
lLa
lBb
lBa
T
t
I
39.3
35.4
39.5
39.5
35.5
35.5
39.5
35.5
t
36.3
4.75
4.80
4.59
4.40
I
5.51
5.49
5.45
5.40
5.37
5.33
5.33
5.26
4.52
50.4
E
4.99 4.90
57.7
I
E
v
41.
40.
39.
38.
37.
P. 281
(2)
spectrum
250
(2)
spectrum
Fief.:
(2)
spectrum
1,6-Dlphenyln30hthalene
Ref.:
300
277
2-Benzylnaphthalene
% Ref.: (2) BpeCtlwm 297
2-Phenylnaphthalene
Ref.:
l-Phenylnaphthalenc
(3)
195
167. fig. 47
(2) spectrum
Ref.: (1) P.
Nsphthalene
NAPHTHALENES
lLa
T
35.0
E
4.05
I
‘G \I
44.
43.
42.
(20)
(10)
(20)
(10)
(3)
(2)
Ref.:
(20)
(10)
(3)
(2)
281
serial
281
spectrum
serial
P.
spectrum
P.
2,2-Dlnaphthyl
Ref.:
serial
%
(3)
281
spectrum
P.
(2)
1,2-Dlnaphthyl
Ref.:
1, I-Dinaphthyl
no.
309
no.
306
n0.
303
260
259
258
T
lLb
E
?
I
3.45
31.8
P
4.15
34.6
I 4.58
E 45.1
(sh.)
(sh.)
lLb
lL.4
‘Bb
IBa
4.20
32.8
3.18
4.99
40.4
30.0
4.62
48.1
48.
47.
46.
45.
Ref.:
Ref.:
P.
501,
501,502
p.
#c
502
Cs Ref.:
Q
(23)
(21)
p.
c=C+=c 501,502
_G
TetrephenJlParlldiphenylquinodiocthane (Tchlchlbablnc’a hydrocarbon)
(22)
(21)
(22)
(21)
=
Tetraphenylparabenzylquinodimethane
BENZENE QUINONOIDS
--t--l-
t-t
ILa
IBb
T
VI
t-t-
l%
T
tt-
lLa
lBb
T E
17.4
E
24.0
37.5
I
4.91
I
4.58
4.14
& 30
Ref.: (26)
(25)
~ef.: (24) p. 279
VII BIPHENYLENES
Ref.: (21) p. 501,502
T ‘19. Tetraph~nylpar~~tllb~~yl~uinodi~~th~~~
VIII
54.
(28)
(21) P. 499
(27)
(21) p. 499
Ref.: (10) serial no. 510
( ~g~g-Bifl"orenyl
Diblphcnylene-ethylene
DIPHENYLENE POLYENBS
-t-t-
21.8
30.8
"b lLe
E 42.0
T lBa
I
I
I
4.37
4.63
4.09
& *
60.
59.
57.
(27)
(24)
P. 276
aerial
(10)
(11)
spectrum
(2)
164,
~cf.: (1)
15
nos.
311
fig.
H2
go
37
L 401
h p.
aromatic
~OLI. 52 & 53
fig.
a cyclic
60
P.
with
158.
serial
p.
FlUOrene
Analogy
(10)
Ref.: (1)
Ref.:
a+ai=c
Blphenylcne-1-dlphenyl-4,4-butadiene
151
T
system
% lCb?
I%
would
‘La
la,
%3
T
E
‘El a(~
4.56
33.8
38.2
44.0
4.70
49.2
I 60.5
n-label
4.63
4.53
38.5 25.8
I 4.G
E 42.0
I% ha
T 1 'ia
lLh
!-
I
T---l23.:*
hb
lL3 1. a
lBb
4.22
32.2
27.5
40.7 Tl)I1 >J1 >I, fib B, La Lb 30.7
4.22
4.21 :slr.)
4O.L 0
4.70
I
3.s
IL,
44.3
E
2.2.4
4.31'
'I.?5 3;.c 31.'_S
4.rc1 47.3
I
4.21 3.07
29.1
:-
4 .'j6
j2.s
4.48
3Y.l
45.0
bt
Ia3
llt, l---r
-t-t
lLa
I%
lBd
I
$ C
69.
68.
67.
(30)
(2) spectrum
538 ‘;
1 28.0
(
3.37
(31)
(2)
spectrum
(2)
(32)
spectrum
xef.:
Ref.:
(31)
(2)
(31)
(2)
spectrum
spectrum
g-phenyl-1,2,5,6-dlbenz
ike.:
g-Phenylfluorene
Ref.:
&
536
535
318
534
q-s+
“““-D~b~~~~fl~~~~ .q$Jg
rter.:
74.
72.
71.
(33)
(2)
(31)
(2)
spec:
spectrum
Ref.:
(38)
(36)
(34)
(37) Acepleladylene
Ref.:
Rubicene
Ref.:
5
!,-phenyl-1,2,3,4,7,8-tribenzofluorene
-t-i-
lLa
l4
“b
T
I----I-
lLa
lLb
lab
”
4.61 3.7: 4.04
34.5 2-.O 20.4
I
4.20 23.6
F
4.69
35.1
I 4.83
E 40.6
*
assignment
17.
Raf.:
(41)
(49)
(2)
spectrum
that
234
.i.cce?tly,
56
the
three
(3’0,
P
30.5
ILb
44.5 37.7
.‘J
E
levels
(36)
% ~
:
Filllams
acepleiadiene
2.41
4.68
4.70
4.94
I
4.7
I
have
3.58
3.34
4.72
I
parallel
reported
Ham and
has
of
who assigned
calculations
lowest
1_
3.
the
26.4
30.2
1L 1 1. %
37.;
1,-b
iI 42.5
‘“.’
Y
-a
1,
l_ -i
Sidman
and
3f
however,
that
472
rig.
analogously,
follows
324
indlcdtl’lg
Acenaphthylene
p01ari.Zati0ns.
r~as’1~eme”ts
‘25)
dccpleiadyiene
Cur
?.ue~j~lh?r~.
-in,:
(34)
6.
SFectrum
(2)
(24)
p.
167,
~c]nce~a~hthylew
(1)
Pyrene’
76.
3cf.:
Cyclohepta
7c.
81.
80.
79.
7s.
(42)
(2)
(40)
p.
(24)
p.
403
Rer.:
(24)
p.
405
3,4-Benzfluoranthene
~ef.:
3-9
spectrum
(2) (24)
p.
(1)
168,
spectrum
2,3-Benzfluxanthene
Ref.:
Flluoranthene
~ef.:
Perinaphthene
235
Ci!$
435
fig.
a
51
H2
E
I
I
2P.f 27.1
lit
34.2
40.1
3.E
4.00
4.55
‘1.57
3.52
23.4
E
3.70
3.91
4.86
I
3.>3
4.53
4.58
4.50
28.0
33.5
40.1
IL,
lBb
lBa
lLa
lLD
%
1Ba
T
lLa
1%
lBb
%
?--lT
T
XI
(43)
(24)
(2)
p.
407
spectrum
Ref.:
(43)
(24)
(2)
P.
H-C-H
408
spectrum
11,12_Benzfluoranthene
Ref.:
lO,ll-Bcnrfluor~nthcnt
FULVENES
83.
82.
543
-I-
lLa xl I% 25.5 33.8 42.5
I
168,
fig.
CI
2.47
2.90
4.23
4.58
90.
89.
(47)
(27)
(27)
(27)
Ref.: (1)
p.
168,
Dlphcnyldibcnzofulvene (Banrhydry lldencE;b
Ref.:
.
52
do fig.
Phcnyldibcnzofulvene (Benzylldene fluorene)
Ref.:
T
E
lLb
4.03 3.98 2.94
36.6
29.6
4.86 44.4
53.6
7-t ‘La
“b
lR.
I
4.14
4.10 HC
I
2.48
3.98
Phcnylbenzofulvene (Benzylldenc lndcnc)
52
4.09
08.
(46)
p.
4.70
4.79
I
(27)
(1)
I
4.33
Ref.:
-&D
4.09
c
4.06
~
4.19
Dlphinylfulvene
(46)
4.14
87.
ref.:
Phenylfulvene
4.50
4.70
86.
(sh.)
(ah.)
193
102.
l
(53)
(49)
(11)
(52)
Indcno-azulene
Ref.:
6-Phenylazulcnc
Ref.:
P-Phenylazulenc
0
This
state
Ref.:
1s
(55)
(541
doubly
degenerate,
0..:.,
..’
CYCLOHEPTATRIENYLIUM ION (Tropyllum ion)
behavlour.
XIII
101.
100.
99.
it
will
have
I
but
? 36.4
1
T IL’
intensity
I
I
I 3.64
I
L,
‘7J-fg-y ‘j-zig
XIV
10-r.
106.
105.
104.
(56)
157)
(57)
a
(57)
Bef.:
(58)
(57)
(2)
spectrum
Trlphenylethylene
Ref.:
Cycloheptadlene-2.6
Benzylldene-l-dibenzo-2,3,6,7
Ref.:
8
156
ir-%
c
H2C
H\
Benzylidene-1-dlbenzo~2,3,6,7 cycloheptatriene-2.4.6
Ref.:
#ethylene-1-dibenko-2,3,6, cycloheptatrlene-2,4,6
~ef.: 46
=1;:
-CYCLOHEPTAPOLYENES,-FULVALENES, & -HEPTAFULVALENES
Dlbenlo-2,3,6,7 Cycloheptatrlene-2,4.
DIBENZO 103.
SPECTRAL
CHARACTERISTICS
OF HYDROCARBONS
195
108.
~ef.:
spectrum
(2)
160
(58) (59) (60) 54.
109.
Dlbiphenylene-ethylene
See Section VIII
Fluorcnylbenzylidcne-1-dibenzo-2,3,6,7 Cyclohcptstrlene-2,4,6
Ref.
:
(21)
p.
500
(61)
110.
Tctrabenzo-2,3,6.7,2’,3’,6’,7’ Heptarulvalene
REFERENCES 1.
2. 8.
4. 6. 6.
7. 8. 9. 10.
T
FOR
E
lBa
46.5
l%
34.5
SPECTRAL
DATA
of Vacuum Ultraviolet Spectra of Oryanic Compounds in Solution, H. B. Klevens and J. R. Platt, reprinted from Technical Report (1953-195X, Part I, Laboratory of Molecular Structure and Spectra Dept. of Physics, University of Chicago. R. A. FRIEDEL AND M. ORCHIN, “Ultraviolet Spectra of Aromatic Compounds,” Wiley, New York, 1951. A. E. GILLAM AND E. S. STERN, “Introduction to Electronic Absorption Spectroscopy in Organic Chemistry.” Edward Arnold, London, 1958. M. R.AMART-LCCAS AND M. J. HOCH, Bull. Sot. Chim. France 2, 1376 (1935). A. E. GILLAM AND D. H. HEY, J. Chef?l. Sot. p. 1170 (1939). M. RAMART-LUCAS, Bull. Sot. Chim. France 61, 289 and 965 (1932). M. RAMART-LUCAS, Bull. Sot. Chim. France 10, 13 (1943). A. HILMER AND E. PAESCH, 2. Physik. Chem. 161, 46 (1932). J. R. PLATT AND H. B. KLEVENS, Chem. Reus. 41, 301 (1947). American Petroleum Institute Research Project 44. National Bureau of Standards. Catalog of IJltraviolet Spectral Datta.
Survey
11. H. B. KLE\.ENiS, J. (‘hew. Ph!/s. 18, l(ifX3 (1950) f2. A. SMAK~-L.\ AXI> A. W.ISHERBI.\N. %. Physik. C’ht~m. Al& 353 r1931). 13. (:. W. WHEIASI,, “ Iteson:tnw in ()rg:rnic Chemintr~.” Wiley, Sew Yorli, 1953. 14. K. W. HAI-SSER, W. ~
I’:tris.
1952.
22. ,4. 1’1-I~Ix.4N. B. PI.LI,x4s, AND Y. HIRSHBERG.
I<. I). I
null.
Sw.
C’h.im.
9.S. W. THEII.AC.KER AND W. OZEGOMYKI,
,?4. b:. CLAR,
“iirom:ttixhe
Frcrtw
p. 707
I<. FISCHER,
I). (;ISSRI.RG
(1051).
Hrr. 73, 899 (19401.
Iiotllenw:ts:i~r,to~~.”
Springer,
Hrrlin, 1952. SW. 63, 3230 (1941). 77, 6022 (1855).
25. E. 1’. C.~RR, I,. W. ~‘ICKETT. ASD 1). \:ORIS, J. Lt)n. I’hetu.
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1910
SPECTRAL
CHBRACTERISTICH
OF HYDROCARBONS
1!>7
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TABLE
I
EMPIRICALFEATURES OF AROMATICSPECTRALTRANSITIONS
1,4\iTt )S
198
have not utilized an exact model but have assumed that all of our systems were amenable to a naive theoretical treatment and, accordingly, have utilized the simple Watt notation, which arises from the perimeter model of condensed aromatic hydrocarbon ring systems. Table I gives spectral features peculiar to vapor phase transitions in catncondensed sis-membered aromatic ring systems, with equivalent) symbols of the various schools indicated. Most of these generalizations were originally noted hy Klevens and I’latt ( 1,B ) . Many of I’lstt’s ‘C”hands have more recently been reinterpreted as ‘R hands. Since ‘C’ transitions are of a quadrupole nature, however, intensity features should lie between the ‘B and ‘L values. The given numerical ranges for the ‘C hands should be considered as tentative. These characteristics can he helpful, with judicious discretion, in classifying bands, but the visualization of approximate molecular symmetry wave functions and Hund’s rules may give a more consistent systematization, especially when accompanied by the intensity information obtainable from the use of transition moments. Icor a more quantitative interpretation of some of the molecules considered herein and many of the more common varieties, profitable use can he made of the tahulations of eigenvalues and eigenvectors given by Coulson and Daudet (8) und by Ham and Ruedenberg (9). The present collection of spectral data was undertaken, following a suggestion by Dr. Ii. Ruedenberg, in conjunct,ion with a theoretical invest,igation of the spectra of a large numher of hydrocarbons by R. Hummel and K. Ruedenberg. RECEIVED:
March
28, 1959. TEXT
1. 2. 3. 4. 5. 6. 7. 8.
9.
R.EFEREKCES
H. B. ELEVENS AXD J.R. ~'I,ATT,J. Chen~. Phys. 17,470 (1949). J. R. PLATT, J. Chem. Phys. 17,484 (1949). N. 8. HAM ANI) K. RUEDEKBERG, J. Chum. Phys. 26, 13 (1956). J. R. PLATT, in “Radiation Biology,” A. Hollaender, ed., Vol. III, Chapter 2. pp. 71-123 McGraw-Hill, New York, 1956. M. J. S. DEWAR AND H. C. LONGKET-HIGGINS, Proc. Phys. Sot. A67, 795 (1954). H. C. LONG~JET-HIGGINS,Aduanres in Chem. Phys. 1, 239-265 (1958). B. I'TLLMAN AND A. PULI.MAN, “Les Theories Electroniques de la Chimie Organiqne.” Masson et Cie., Paris, 1952. C. A. C~ULSON AND R. I~AUDEL, eds., “Dictionary of Values of Molecular Constants.” Vols. I, II, III. Mathematical Institute, Oxford, and the Centre dechimie Thkorique de France, Paris, 1959. N. S. HAM AND Ii. RUEDEKBERG, 1. Chew. Phys. 29, 1199 (1958).