Aqua dissociation nature of cesium hydroxide
Srinivas Odde, Chaeho Pak, Han Myoung Lee, Kwang S. Kim, and Byung Jin Mhin
Citation: The Journal of Chemical Physics 121, 204 (2004); doi: 10.1063/1.1757438
View online: http://dx.doi.org/10.1063/1.1757438
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JOURNAL OF CHEMICAL PHYSICS
VOLUME 121, NUMBER 1
1 JULY 2004
Aqua dissociation nature of cesium hydroxide
Srinivas Odde, Chaeho Pak, Han Myoung Lee, and Kwang S. Kima)
Department of Chemistry, National Creative Research Initiative Center for Superfunctional Materials,
Division of Molecular and Life Sciences, Pohang University of Science and Technology, San 31, Hyojadong,
Namgu, Pohang 790-784, Korea
Byung Jin Mhin
Department of Chemistry, Pai Chai University, 439-6 Domadong, Seoku, Daejeon 302-735, Korea
共Received 9 March 2004; accepted 9 April 2004兲
To understand the mechanism of aqueous base dissociation chemistry, the ionic dissociation of
cesium–hydroxide in water clusters is examined using density functional theory and ab initio
calculations. In this study, we report hydrated structures, stabilities, thermodynamic quantities,
dissociation energies, infrared spectra, and electronic properties of CsOH•(H2 O) n⫽0 – 4 . With the
addition of water molecules, the Cs–OH bond lengthened significantly from 2.46 Å for n⫽1 to 3.08
Å for n⫽4, which causes redshift in Cs–O stretching frequency. It is found that three water
molecules are needed for the dissociation of Cs–OH, in contrast to the case of strong acid
dissociation which requires at least four water molecules. However, the dissociation for n⫽3 could
be considered as incomplete because a very weak CS...OH stretch mode is still present, while that
for n⫽4 is complete since the Cs...OH mode no longer exists. This study can be related with
hydration chemistry of cations and anions, and extended into the intra- and intercharge-transfer
phenomena. © 2004 American Institute of Physics. 关DOI: 10.1063/1.1757438兴
I. INTRODUCTION
ously, theoretical work is more appropriate. Consequently,
we carried out extensive ab initio Møller–Plesset perturbation theory 关MP2兴, coupled-cluster single double triple
关CCSD共T兲兴 and density functional theory 共DFT兲 calculations
on cesium hydroxide in water, to obtain the accurate energetics, vibrational frequencies, structural stabilities, ionization
potential, dissociation energy, and thermodynamic quantities.
Unlike aqueous acid dissociation chemistry,1 little research has been done on aqueous base dissociation chemistry. Therefore, we are interested in investigating thermochemical properties of gaseous alkali metal hydroxides in
water. The hydration phenomena of halide anions of strong
acids2 and the alkali metal cations of strong bases3 have been
well investigated since these ions interact with various neutral ligands such as water in a wide variety of physical,
chemical, and biological phenomena.4 In this study, we investigate the hydration of cesium hydroxide 共CsOH兲.
Cs137 is the major component of nuclear wastes due to its
long half-life time. Therefore, a lot of effort has been made
to get rid of the Cs⫹ ion.5,6 What’s more, CsOH and CsOH
•H2 O are widely used in synthetic organic chemistry as catalysts, such as in O–alkylation of alcohols,7 N-alkylation to
obtain secondary amines,8 alkylation of aldehydes, ketones,
nitriles,9 addition of nitriles to alkynes,10 addition of alcohols
and secondary amine derivatives to alkynes and styrene,11
enantioselective alkylation,12 desilylation to form carbon
anions,13 and synthesis of tetrathiafulvalene thiolates.14
In order to understand the CsOH•(H2 O) n dissociation
phenomena, the clusters of hydrated cesium hydroxide need
to be extensively investigated, depending on the cluster size
(n⫽0 – 4). The solvation of a base can be monitored by
inspecting the cesium–oxygen distance as we add water molecules. Therefore, one of the important aspects of this study
is to find out how many water molecules are needed for
dissociative ionization of base. Since cesium is very reactive
due to its size, which is known to react even with ice vigor-
II. THEORETICAL PROCEDURES
The equilibrium structures of the CsOH•(H2 O) 0 – 4 were
calculated using the DFT with Becke’s three parameter exchange potential and Lee, Yang, and Parr correlation functional 共B3LYP兲,15 and the second-order MP2. For the basis
sets, we used 6-311⫹⫹G** 关 sp 兴 at B3LYP and the
aug-cc-pVDZ⫹diffuse(2s2 p/2s) basis set at MP2 and
CCSD共T兲 calculations. Here 关sp兴 means the diffuse sp functions are added only for the oxygen atom with 1/8 scaled
FIG. 1. B3LYP/6-311⫹⫹G** 关 sp 兴 optimized conformations of the
Cs–OH(H2 O) 0 – 4 .
a兲
Author to whom correspondence should be addressed. Electronic mail:
[email protected]
0021-9606/2004/121(1)/204/5/$22.00
204
© 2004 American Institute of Physics
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J. Chem. Phys., Vol. 121, No. 1, 1 July 2004
Aqua dissociation of cesium hydroxide
205
TABLE I. Geometrical parameters and dissociation energies of water, hydroxide anion, and monomeric cesium
hydroxide.a
D0
Geometrical parameters
Monomer
H2 O
OH⫺
CsOH
Parameter
r(OH)
⬔HOH
r(OH)
r(Cs...O)
rOH
⬔CsOH
␻1
␻2
a
B3LYP
MP2
Expt.
0.962
105.0
0.966
2.446
0.960
180
354
3731
0.966
103.9
0.973
2.460
0.966
180
340
3582
0.957
104.5
¯
2.391
0.95⫾0.01
180
400⫾80,336
3700
B3LYP
MP2
¯
¯
¯
⫺131.24
¯
¯
¯
¯
¯
¯
¯
⫺127.96
¯
¯
¯
¯
a
Experimental values are from Refs. 20–30. Distances are in angstrom, angles in degrees; dissociation energy
(D 0 ) in kcal/mol. B3LYP and MP2 denote B3LYP/6-311⫹⫹G** 关 sp 兴 and MP2/aug-cc-pVDZ⫹(2s2p/2s),
respectively.
exponents of the outermost sp functions of the
B3LYP/6-311⫹⫹G** basis set, while the (2s2p/2s) at
MP2 level indicates that the (2s2p/2s) is a diffuse basis set
with 1/8 scaled exponents of the outermost sp functions of
the aug-cc-pVDZ basis set.16 For the Cs basis sets, we used
the diffuse basis set with the effective core potential of
Lajohn et al.17 All of our CCSD共T兲 results are single point
energy calculations at the MP2 geometries. Enthalpies and
free energies were obtained using standard expression for
ideal gases at 298 K and 1 atm pressure. The calculations
were carried out using the GAUSSIAN 03 suite of program.18
Most of the figures presented here were drawn using the
Pohang Sci-Tech Molecular Modeling 共POSMOL兲 and some
available graphic packages.19
III. RESULTS AND DISCUSSION
Based on the previous experimental and theoretical studies on alkali–metal hydroxides20–34 and aqua–cesium water
clusters,35 we contemplate the possible conformation of
CsOH•(H2 O) n⫽1 – 4 and their systematic study on energetics
and spectral properties of CsOH by adding up to four water
molecules. Figure 1 shows all the optimized conformations
of CsOH•(H2 O) 0 – 4 at B3LYP/6-311⫹⫹G** 关 s p 兴 level of
theory. Table I lists the geometrical parameters and dissociation energies of monomeric species namely CsOH, OH⫺ ,
and H2 O. Tables II, III, and IV show the interaction energies
at B3LYP, MP2, and CCSD共T兲 levels of theory, respectively.
Table V lists conformational characteristics and rotational
constants. Table VI lists electronic properties including ionization potentials and charge-transfer-to-solvent 共CTTS兲 energies. Table VII lists scaled frequencies.
A. Structures and energetics
Due to its size and reactivity, there are limited numbers
of studies both experimentally and theoretically on the CsOH
molecule, and furthermore, no work has been done with water clusters. The first microwave spectrum of the CsOH
structure 共Cs–O distance of 2.40⫾0.01 Å with fixed O–H
bond distance of 0.97⫾0.05 Å) was reported by Kuczkowski and Lide.21 Their later study22 refined the results as
the Cs–O distance of 2.391⫾0.002 Å with fixed O–H bond
distance of 0.96⫾0.01 Å. Then in 1994, Brown et al.23 reported a Cs–O distance of 2.393⫾0.012 Å with a rather long
O–H bond distance of 0.992 Å. There are a few theoretical
works available on this molecule. The first theoretical work
共based on the configuration interactions with single and
double excitations level of theory with valence basis set with
effective core potential based on averaged Dirac–Fock wave
functions for Cs兲 was done by Bauschlicher and Langhoff.20
They reported the Cs–OH bond distance to be 2.419 Å at
fixed O–H bond length. Then in 1994, Stiakaki et al.24 did a
molecular orbital study and reported a Cs–OH bond distance
of 2.447 Å. The latest work was done by Lee and Wright25 in
which they report the Cs–OH bond distance to be 2.635 Å
with CCSD共T兲 level of theory with LANL2 关 9s8 p3d2 f 兴 basis set for Cs and aug-cc-pVTZ basis set for O and H.
TABLE II. B3LYP/6-311⫹⫹G** 关 sp 兴 interaction energies of Cs–OH(H2 O) 1 – 4 clusters in kcal/mol.
n
Conformer
⫺⌬E e
⫺⌬E 0
⫺⌬H
⫺⌬G
1
2
1U11
2U22
2U11
3D33
3U12
3U22
4D44
4D33
4U22
4D43
19.44
37.95
33.73
53.54
51.14
51.71
63.94
66.00
64.55
58.39
18.18
34.37
31.50
47.99
44.55
45.99
55.16
58.17
56.48
51.94
18.90
35.88
33.72
49.90
47.04
48.15
57.87
59.25
59.25
54.02
11.61
18.68
15.27
24.36
19.44
22.17
22.12
24.48
24.48
21.73
3
4
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206
Odde et al.
J. Chem. Phys., Vol. 121, No. 1, 1 July 2004
TABLE III. MP2/aug-cc-pVDZ⫹(2s2p/2s) interaction energies for lowest
energies of CsOH(H2 O) 1 – 4 clusters in kcal/mol.
TABLE V. CCSD(T)/aug-cc-pVDZ⫹(2s2p/2s) interaction energies for
the lowest energies of CsOH(H2 O) 1 – 4 clusters in kcal/mole.a
Conformer
⫺⌬E e
⫺⌬E 0
⫺⌬H
⫺⌬G
Conformer
⫺⌬E e
⫺⌬E 0
⫺⌬H
⫺⌬G
1U11
2U22
3D33
3U22
4D33
4U22
20.73
39.98
56.79
53.69
69.17
66.29
19.33
36.39
51.50
48.18
61.39
58.36
20.16
37.87
53.00
50.27
63.95
61.07
12.21
20.87
27.15
24.50
29.44
26.80
1U11
2U22
3D33
3U22
4D33
4U22
19.80
38.27
54.34
51.14
66.18
63.09
18.40
34.69
48.57
45.63
58.27
55.16
19.23
36.16
50.56
47.71
60.83
57.87
11.28
19.17
24.70
21.95
26.31
23.59
a
Zero point energies and thermal energies used the MP2/aug-cc-pVDZ
⫹(2s2p/2s) values.
Although our DFT and MP2 results are rather different
from the electron diffraction study by Girichev et al.26 and
the latest ab initio study by Lee and Wright,25 our results are
very close to the earlier theoretical and experimental results,
off only by 0.055 Å with B3LYP and 0.069 Å with MP2
compared to the microwave study22 共see Table I兲. Nevertheless, for the purpose of this study, the difference in Cs–OH
bond distance with the latest ab initio work is inconsequential as we are interested in relative change in the Cs–OH
bond distance upon addition of water molecules. We feel that
our CCSD(T)/aug-cc-pVDZ⫹diffuse//MP2/aug-cc-pVDZ
⫹diffuse level of theory is sufficient enough to explain the
dissociation mechanism of CsOH in water molecules.
Figure 1 shows the B3LYP/6-311⫹⫹G** 关 sp 兴 optimized structures of CsOH•(H2 O) n⫽1 – 4 . For notations
‘‘nUn 1 n 2 ’’ and ‘‘nDn 1 n 2 ,’’ n is the number of water molecules, and n 1 and n 2 are the hydration numbers of Cs⫹ and
OH, respectively, and U/D indicates the undissociated/
dissociated state. The number of minimum energy structure
increases dramatically as the cluster size increases. Therefore, we have searched for numerous conformers based on
our previous experiences in generating many different conformers of various kinds of molecular clusters.36 With successive addition of water molecules, the hydrogen bonding
interaction and coordination number of the metal atom increase, resulting in the Cs–OH bond distance gradually increasing from mono- to tetra-hydrated systems:
1U11 (2.60 Å) – 4D33 (3.08 Å). Similarly, we found the
noticeable decrement in Cs–O stretching frequencies. Unlike
our earlier studies on acid dissociation where it requires at
least four water molecules to have a stable dissociation complex, CsOH requires only three water molecules. The dissociation energy (D e ) of the pure CsOH was calculated at
B3LYP and MP2 levels of theory are ⫺131.2 and ⫺128.0
kcal/mol, respectively. The calculated dipole moment of
CsOH at the MP2/aug-cc-pVDZ⫹diffuse level is 7.4 D,
which is in good agreement with the experimental value of
7.1 D.22 We also report neutral state dipole moments for all
the minimum energy clusters in Table IV.
The interaction energies of CsOH•(H2 O) 1 – 4 clusters at
the B3LYP/6-311⫹⫹G** 关 sp 兴 level of theory shows that
the lowest-energy conformers of mono- to di-hydrated cesium hydroxide are undissociated, whereas stable conformers
are found to be dissociated with three water molecules or
more. With four water molecules, all of them were dissociated except for 4U22. Based on our DFT and MP2 results,
the lowest energy conformers for CsOH•(H2 O) n where n
⫽1 – 4 are 1U11, 2U22, 3D33, and 4D33, respectively. For
n⭓3, the dissociated conformers are more stable than the
undissociated conformers.
B. Electronic properties
The ionization potentials 共IPs兲 (IPv : vertical IP, and
IPK : IP by Koopman’s theorem兲 of CsOH•(H2 O) 1 – 4 are
listed in Table VI at the MP2/aug-cc-pVDZ⫹(2s2p/2s)
level. The IP shows an interesting trend, the IPs of pure
CsOH is 7.67 eV, which is very close to the Emel’yanov
et al.’s28 result of 7.21⫾0.04, and Gorokhov et al.’s29 results
of 7.40⫾0.15 eV. This value is much smaller than the water
monomer 14.79 eV. With the successive addition of water
molecules, the IPv of CsOH increases by 0.83, 1.43, 1.82,
and 2.05 eV for 1U11, 2U22, 3D33, and 4D33 共the lowestenergy conformations兲, respectively. As previously studied,
the alkali–metal hydroxide ions can also provide interesting
charge-transfer-to-solvent 共water兲 via the available excitation
process. Therefore, their vertical excitation energies at the
TABLE IV. MP2/aug-cc-pVDZ⫹(2s2p/2s) conformational characteristics and geometric parameters 关distances (r/Å) and rotational constants 共A, B, C in GHz兲兴 for the low energy clusters CsOH(H2 O) 1 – 4 . a
Rotational constants
n
Conformer
No. HB/coord
r Cs...OH
r Cs...O1
r Cs...O2
A
B
C
1
2
3
1U11
2U22
3U22
3D33
4U22
4D33
1/2
2/3
3/3
3/3
4/3
4/3
2.60
2.79
2.82
3.02
2.81
3.08
2.883
2.922
2.956
2.928
2.992
2.949
—
—
3.268
—
3.333
3.297
9.005
2.831
1.862
1.73
1.273
1.182
2.883
2.256
1.529
1.317
1.017
1.069
2.185
1.413
0.945
1.316
0.760
0.895
4
r Cs...O1 and r Cs...O2 are the nearest oxygen to cesium distances in 共Å兲 in the primary and secondary hydration
shell, respectively.
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a
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J. Chem. Phys., Vol. 121, No. 1, 1 July 2004
Aqua dissociation of cesium hydroxide
207
TABLE VI. Electronic properties of CsOH(H2 O) 1 – 4 .
Conformer
IPv
IPK
␮ neut
CsOH(H2 O) 1 – 4
1U11
2U22
3D33
3U22
4D33
4U22
8.50
9.10
9.49
9.37
9.72
9.47
9.68
10.34
10.83
10.59
11.05
10.75
5.98
4.47
2.79
3.51
2.22
3.59
RPA
␦ E CTTS
(f )
4.32
4.64
5.28
4.68
5.09
4.52
共0.063兲
共0.014兲
共0.011兲
共0.008兲
共0.028兲
共0.007兲
CI共S兲
␦ E CTTS
(f )
6.50
7.09
7.48
7.32
7.66
7.44
共0.034兲
共0.038兲
共0.038兲
共0.040兲
共0.039兲
共0.044兲
H-L
␦ E gap
9.63 共4.57兲
10.32 共5.29兲
10.84 共5.87兲
10.59 共5.63兲
11.06 共6.11兲
10.75 共5.80兲
IPv , IPK , and ␮ neut are vertical and Koopman’s IPs 共in eV兲 and neural-state dipole moment 共in Debye兲 at the
RPA
CI(S)
MP2/aug-cc-pVDZ⫹(2s2p/2s) level. IPv s of pure CsOH are 7.67 eV. E CTTS
and E CTTS
are charge-transferto-solvent energies 共in eV兲 at RPA-B3LYP/6-311⫹⫹G** 关 sp 兴 and CI(S)/aug-cc-pVDZ⫹(2s2p/2s) levels,
and the values in parentheses are oscillator strengths 共f in a.u.兲. ␦ E gap is the HOMO–LUMO energy gap 共eV兲
at the MP2/aug-cc-pVDZ⫹(2s2p/2s) level and the values in parentheses are at the RPA-B3LYP/6-311⫹
⫹G** 关 sp 兴 level.
a
MP2/aug-cc-pVDZ⫹(2s2p/2s) optimized geometries are
interesting in terms of absorbed photoenergies in photoelectron spectroscopy or ultraviolet absorption experiments.
RPA
and
Table VI lists the vertical excitation energies ( ␦ E CTTS
CI(S)
␦ E CTTS) with their oscillator strengths 共f 兲 of lowest-energy
Cs–OH (H2 O) 1 – 4 at RPA-B3LYP/6-311⫹⫹G** 关 sp 兴 and
CI(S)/aug-cc-pVDZ⫹(2s2p/2s) levels. Both results are
consistent. These excitation energies have a strong relation to
the energy gap ( ␦ E gap) between the highest occupied molecular orbital 共HOMO兲 and the unoccupied molecular orbital 共LUMO兲. From these electronic properties we can expect weak electron affinity of these bases.
C. Vibrational frequencies
The O–H vibrational spectra of hydrated molecular clusters provide important information of hydrated structure.
Therefore, here we provide the O–H spectra as well as Cs–O
vibrational frequencies to help facilitate the experimental investigation of the dissociation phenomena of alkali metal
hydroxide 共Table VII and Fig. 2兲. Experimentally, pure
Cs–O and O–H stretch modes were observed around 336
and 3700 cm⫺1, respectively. Our calculated scaled frequencies for Cs–O and O–H are 354 cm⫺1 共340 cm⫺1兲 and 3731
cm⫺1 共3582 cm⫺1兲 at B3LYP and 共MP2兲, respectively. Lee
and Wright25 calculated the Cs–O stretch frequency at 346
cm⫺1 at the CCSD共T兲 level. There is a good agreement between the harmonic frequency of 340 cm⫺1 and the experimental fundamental value of 336 cm⫺1. In the case of conformation 1U11, the calculated B3LYP 共MP2兲 scaled
frequencies by the scale factor of 0.96 are 225, 2368, 3739,
3749 共225, 2327, 3714, 3743兲 cm⫺1 for the stretch modes of
Cs–O, O–H...OH⫺ , CsO–H, O–Hd , respectively. In conformation 2U22, the Cs–O stretch frequency decreases to 127
cm⫺1 共76 cm⫺1兲. The O-H...OH⫺ stretch frequencies are predicted at 2524, 2666 共2555, 2688兲 cm⫺1; the CsO–H stretch
frequency at 3732 共3715兲 cm⫺1, the O–Hd stretch frequency
at 3743, 3745 共3740, 3741兲 cm⫺1. In stable dissociated conformation 3D33, the Cs–O stretch mode almost disappeared.
The undissociated conformations 3U22 and 4U22 show the
Cs–O frequency at 156 共148兲 cm⫺1, and 183 共180兲 cm⫺1
respectively. In stable dissociated conformation 4D33, the
Cs–O stretch mode disappears.
TABLE VII. Predicted frequencies in 共cm⫺1兲 of Cs–OH(H2 O) 1 – 4 conformers at B3LYP/6-311⫹⫹G** 关 sp 兴 and MP2/aug-cc-pVDZ⫹(2s2p/2s)
scaled by 0.96, respectively.
Conformer
1U11
2U22
3D33
3U22
4D33
4U22
B3LYP
MP2
225
2368
3739
3749
127
2524
2666
3732
3743
3745
62
2710
2715
2886
3724
3744
3745
3746
156
2209
2735
3129
3726
3732
3741
3743
2453
2780
2907
3235
3713
3730
3741
3743
3744
183
2379
2547
3142
3153
3713
3728
3731
3737
3741
225
2327
3714
3743
148
2555
2688
3715
3740
3741
88
2767
2768
2923
3698
3741
3742
3743
148
2138
2765
3222
3711
3726
3741
3741
2500
2830
2949
3393
3691
3719
3737
3739
3740
180
2367
2566
3176
3247
3699
3713
3719
3737
3742
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208
J. Chem. Phys., Vol. 121, No. 1, 1 July 2004
FIG. 2. MP2/aug-cc-pVDZ⫹(2s2p/s) infrared spectra 关scaled harmonic
frequencies ( ␻ s ); scale factor⫽0.96] O–H stretching modes of
Cs–OH(H2 O) 1 – 4 . The ( ␻ s ) 共in cm⫺1兲 for the Cs–OH(H2 O) 1 – 4 are listed in
Table VII.
With the successive addition of water molecules, the
Cs–O stretch mode decreases gradually. Even though we
find that a stable dissociation at n⫽3, 3D33 has the weak
stretch mode. There is no mode corresponding to Cs–O
stretch for n⫽4. For all the undissociative conformations
(1U11,2U11,3U22,4U22), the scaled CsO–H stretch mode
appears at 3714, 3715, 3711, and 3699 cm⫺1 at the
MP2/aug-cc-pVDZ⫹(2s2 p/2s) level. For the dissociated
conformations of 3D33 and 4D33, the OH⫺ anion is stabilized by the hydrogen bonding interaction of adjacent water
molecules, resulting in slightly redshifted stretch modes of
3698 and 3691 cm⫺1, respectively, at the MP2/
aug-cc-pVDZ⫹(2s2p/2s) level.
IV. CONCLUDING REMARKS
Unlike aqueous acid dissociation which requires at least
four water molecules, CsOH requires only three water molecules to form a stable dissociation complex. The stretch
mode of Cs–O disappears as the clusters change from undissociated to dissociated complexes with increasing size, and
we notice a redshift in the O–H stretch mode of the OH⫺
anion. This study would be helpful in facilitating experimental studies on hydrated alkali–metal hydroxide clusters to
understand more about the dissociation trends in water.
ACKNOWLEDGMENTS
This work was supported by Creative Research Initiatives of Korean Ministry of Science and Technology, and
BK21.
1
S. Re, Y. Osamura, Y. Suzuki, and H. F. Schaefer III, J. Chem. Phys. 109,
973 共1998兲; M. Farnik, M. Weimann, and M. A. Suhm, ibid. 118, 10120
共2003兲; E. M. Cabaleiro-Lago, J. M. Hermida-Ramon, and RodriguezOtero, ibid. 117, 3160 共2002兲; S. Odde, B. J. Mhin, S. Lee, H. M. Lee, and
K. S. Kim, ibid. 共in press兲.
2
H. M. Lee and K. S. Kim, J. Chem. Phys. 117, 706 共2002兲; H. M. Lee,
Odde et al.
S. B. Suh, and K. S. Kim, ibid. 118, 9981 共2003兲; H. M. Lee, S. Lee, and
K. S. Kim, ibid. 119, 187 共2003兲; J. Baik, J. Kim, D. Majumdar, and K. S.
Kim, ibid. 110, 9116 共1999兲; H. M. Lee and K. S. Kim, Mol. Phys. 100,
875 共2002兲.
3
C. J. Weinheimer and J. M. Lisy, J. Chem. Phys. 105, 2938 共1996兲; T. D.
Vaden, B. Forinash, and J. M. Lisy, ibid. 117, 4628 共2002兲; H. M. Lee, J.
Kim, S. Lee, B. J. Mhin, and K. S. Kim, ibid. 111, 3995 共1999兲; J. Kim, S.
Lee, S. J. Cho, B. J. Mhin, and K. S. Kim, ibid. 102, 839 共1995兲.
4
J. J. R. Fraústo da Silva and R. J. P Williams, The Biological Chemistry of
the Elements 共Clarendon, Oxford, U.K., 1991兲.
5
T. B. Lindemer, T. M. Besmann, and C. E. Johnson, J. Nucl. Mater. 100,
178 共1981兲.
6
J. F. Ahearne, Phys. Today 50, 24 共1997兲; J. S. Bradshaw and R. M. Izatt,
Acc. Chem. Res. 30, 338 共1997兲; T. J. Haverlock, P. V. Bonnesen, R. A.
Sachleben, and B. A. Moyer, Radiochim. Acta 76, 103 共1997兲; E. P.
Horwitz, R. Chiarizia, and M. L. Dietz, Solvent Extr. Ion Exch. 10, 313
共1992兲.
7
E. E. Dueno, F. Chu, S.-I. Kim, and K. W. Jung, Tetrahedron Lett. 40,
1843 共1999兲.
8
R. N. Salvatore, A. S. Nagle, S. E. Schmidt, and K. W. Jung, Org. Lett. 1,
1893 共1999兲.
9
D. Tzalis and P. Knochel, Angew. Chem. 38, 1463 共1999兲.
10
C. Koradin, A. Rodriguez, and P. Knochel, Synlett. 10, 1452 共2000兲.
11
D. Tzalis, C. Koradin, and P. Knochel, Tetrahedron Lett. 40, 6193 共1999兲.
12
E. J. Corey, M. C. Noe, and F. Xu, Tetrahedron Lett. 39, 5347 共1998兲.
13
J. Busch-Petersen, Y. Bo, and E. J. Corey, Tetrahedron Lett. 40, 2065
共1999兲.
14
J. L. Segura and N. Martin, Angew. Chem. 113, 1416 共2001兲.
15
A. D. Becke, J. Chem. Phys. 98, 1372 共1993兲; 98, 5648 共1993兲; C. Lee, W.
Yang, and R. G. Parr, Phys. Rev. B 37, 785 共1988兲.
16
J. Kim, H. M. Lee, S. B. Suh, D. Majumdar, and K. S. Kim, J. Chem.
Phys. 113, 5259 共2000兲; H. M. Lee and K. S. Kim, ibid. 114, 4461 共2001兲;
H. M. Lee, D. Kim, and K. S. Kim, ibid. 116, 5509 共2002兲.
17
L. A. Lajohn, P. A. Christiansen, R. B. Ross, T. Atashroo, and W. C.
Ermler, J. Chem. Phys. 87, 2812 共1987兲, and reference therein.
18
M. J. Frisch, G. W. Trucks, H. B. Schlegel, et al., GAUSSIAN 03, Revision
A.1, Gaussian, Inc., Pittsburgh, PA, 2003.
19
S. J. Lee and K. S. Kim, POSMOL, Reg. No. 2000-01-12-4239 共Postech
Licensing Center, Pohang, Korea, 2000兲, Anonymous ftp address 具ftp://
csm50.postech.ac.kr/posmol典.
20
C. W. Bauschilcher, Jr. and S. R. Langhoff, J. Chem. Phys. 84, 901 共1986兲.
21
R. L. Kuczkowski and D. R. Lide, Jr., J. Chem. Phys. 44, 3131 共1966兲.
22
D. R. Lide and R. L. Kuczkowski, J. Chem. Phys. 46, 4768 共1967兲.
23
R. D. Brown, P. D. Godfrey, B. Kleibömer, and D. J. McNaughton, J. Mol.
Struct. 327, 99 共1994兲.
24
M.-A. Stiakaki, A. C. Tsipis, C. A. Tsipis, and C. E. Xanthopoulos, Chem.
Phys. 189, 533 共1994兲.
25
P. F. Lee and T. G. Wright, J. Phys. Chem. A 107, 5233 共2003兲.
26
G. V. Girichev, S. B. Lapshina, and V. I. Tumanova, J. Struct. Chem. 31,
966 共1991兲.
27
N. Acquista, S. Abramowitz, and D. R. Lide, J. Chem. Phys. 49, 780
共1968兲.
28
A. M. Emel’yanov, A. V. Gusarov, L. N. Gorokhov, and N. A. Sadovnikova, Theor. Exp. Chem. 3, 226 共1967兲 关Teor. Eksp. Khim. 3, 126 共1967兲兴.
29
L. N. Gorokhov, A. V. Gusarov, and I. G. Panchenkov, Russ. J. Phys.
Chem. 44, 269 共1970兲 关Zh. Fiz. Khim. 44, 150 共1970兲兴.
30
D. R. Lide and R. L. Kuczkowski, J. Chem. Phys. 50, 3080 共1969兲.
31
D. E. Jenson, J. Phys. Chem. 74, 207 共1970兲; D. E. Jenson and P. J.
Padley, Trans. Faraday Soc. 62, 2132 共1966兲.
32
D. H. Cotton and D. R. Jenkins, Trans. Faraday Soc. 65, 1537 共1969兲.
33
J. A. Tainer, V. A. Roberts, and E. D. Getzoff, Curr. Opin. Biotechnol. 2,
582 共1991兲.
34
A. K. Katz, J. P. Glusker, S. A. Beebe, and C. W. Bock, J. Am. Chem. Soc.
118, 5752 共1996兲.
35
D. Feller, E. D. Glendening, and D. E. Woon, J. Chem. Phys. 103, 3526
共1995兲.
36
H. M. Lee, S. B. Suh, J. Y. Lee, P. Tarakeshwar, and K. S. Kim, J. Chem.
Phys. 112, 9759 共2000兲; K. S. Kim, M. Dupuis, G. C. Lie, and E. Clementi, Chem. Phys. Lett. 131, 451 共1986兲; K. S. Kim, B. J. Mhin, U.-S.
Choi, and K. Lee, J. Chem. Phys. 97, 6649 共1992兲; J. Kim and K. S. Kim,
ibid. 109, 5886 共1998兲; J. Kim, S. B. Suh, and K. S. Kim, ibid. 111, 10077
共1999兲; K. S. Kim, P. Tarakeshwar, and J. Y. Lee, Chem. Rev. 共Washington, D.C.兲 100, 4145 共2000兲.
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