Phthalocyanine Adsorption to Graphene on Ir(111): Evidence for Decoupling from Vibrational Spectroscopy M

Home , Phthalocyanine

Supplemental material to: Phthalocyanine adsorption to graphene on Ir(111): Evidence for decoupling from vibrational spectroscopy M. Endlich,1, a) S. Gozdzik,1 N. Néel,1 A. L. da Rosa,2, 3 T. Frauenheim,2 T. O. Wehling,2, 4 and J. Kröger1, b) 1)Institut für Physik, Technische Universität Ilmenau, D-98693 Ilmenau, Germany 2)Bremen Center for Computational Materials Science, University Bremen, D-28359 Bremen, Germany 3)Federal University of Minas Gerais, Department of Physics, 31270-901 Belo Horizonte, MG, Brazil 4)Institute for Theoretical Physics, University Bremen, D-28359 Bremen, Germany

a)Electronic mail: [email protected] b)Electronic mail: [email protected]

1 Fig. S1. Relaxed geometry of free H2Pc with indicated Cartesian coordinates x, y. The z axis is oriented perpendicular to the xy plane. Speciﬁc molecule groups and atoms are labeled.

The free H2Pc molecule (Fig. S1) exhibits D2h symmetry. The symmetry classes, Q, of this group together with the characters, χ, of speciﬁc reducible representations are summarized in Table SI.

D2h E C2(z) C2(y) C2(x) I σ(xy) σ(xz) σ(yz) Γ 168 2 0 −2 0 58 4 2

Tab. S I. Symmetry operations of the D2h point group (the group elements are divided into classes, i.e., E: identity, C2: two-fold rotation with relevant rotation axes given in parentheses, I: inversion, σ: reﬂection with relevant mirror planes given in parentheses). Γ represents a set of speciﬁc reducible representations of the symmetry operations whose characters are given in the bottom row.

Using the reduction formula,1

1 a = N · χ(R) · χ (R), (1) i h X i Q with h the number of group elements, R a group element, N the number of operations in the class, χi the character of R in the ith irreducible representation (Table SII), the number of times, ai, a speciﬁc irreducible representation appears in the reducible representation may

2 D2h E C2(z) C2(y) C2(x) I σ(xy) σ(xz) σ(yz)

Ag 11 1 11 1 11

B1g 1 1 −1 −1 1 1 −1 −1

B2g 1 −1 1 −1 1 −1 1 −1

B3g 1 −1 −1 1 1 −1 −1 1

Au 1 1 1 1 −1 −1 −1 −1

B1u 1 1 −1 −1 −1 −1 1 1

B2u 1 −1 1 −1 −1 1 −1 1

B3u 1 −1 −1 1 −1 1 1 −1

Tab. SII. Character table of the D2h point group. Ag, ..., B3u denote irreducible representations

of the D2h elements.

be calculated. As a result, the symmetry of vibrational modes of free H2Pc may be described as

Γ=13 Au + 15 B1u + 28 B2u + 28 B3u + 29 Ag + 28 B1g + 14 B2g + 13 B3g. (2)

Upon adsorption of H2Pc to Ir(111) the adsorbate complex exhibits Cs symmetry. The

Cs character table is presented in Table SIII.

Cs E σ(xz) A′ 1 1 A′′ 1 −1

Tab. SIII. Symmetry operations of the Cs point group (E: identity, σ(xz): reﬂection at xz plane). ′ ′′ A and A denote irreducible representations of the Cs elements.

To relate vibrational modes of the adsorbate complex to the modes of the gas-phase 1 molecule correlation tables may be used. Table IV shows the correspondence of D2h ir- 1 reducible representations with those of Cs. According to the selection rules for the dipole scattering regime only those vibrational excitations from the ground state to the ﬁrst excited state of an eigenmode will be observed that belong to the totally symmetric representations ′ 1 A . Consequently, Ag, B2g and B3u vibrational modes will additionally become dipole active and visible in specular spectra upon symmetry reduction.

3 D2h Ag Au B1g B1u B2g B2u B3g B3u ′ ′′ ′′ ′ ′ ′′ ′′ ′ Cs A A A A A A A A

Tab. SIV. D2h – Cs correlation table.

The vibrational energies of modes belonging to the irreducible representations of free 2 3 H2Pc (Table SII) were calculated within density functional theory using Gaussian09 with the hybrid functional B3LYP4 and the Gaussian basis set 6−311G.5,6 The vibrational modes were calculated in the harmonic approximation with the molecule symmetry ﬁxed to D2h. The calculated energies together with the mode symmetry classes are listed in Table SV. To compare calculations with experimental data the calculated energies were multiplied by 0.955, a factor that is similar to previous ﬁndings.7–9

4 No. Sym. Energy Infrared Raman Mode assignment calc. corr. intensity intensity

(meV) (km mol−1) (1027 A4 kg−1)

001 B1u 2.632 2.513 0.003 (⊥) twisting (all isoindole arms)

002 B1u 5.035 4.809 1.938 (⊥) wagging (whole molecule)

003 Au 6.754 6.450 twisting (whole molecule)

004 B2g 6.816 6.509 0.132 twisting (whole molecule)

005 B3g 7.487 7.150 0.097 twisting (whole molecule)

006 B1g 9.781 9.341 2.033 scissoring (whole molecule)

007 B2g 14.881 14.212 5.388 twisting (all isoindole arms)

008 B2u 15.158 14.476 3.504 (k) scissoring (2 opposite isoindole arms)

009 B3u 15.285 14.597 4.461 (k) scissoring (2 opposite isoindole arms)

010 Au 15.462 14.766 twisting (all isoindole arms)

011 B3g 16.092 15.368 6.467 twisting (all isoindole arms)

012 Ag 16.389 15.652 18.845 asymm. stretching (whole molecule)

013 B1u 17.506 16.718 0.414 (⊥) twisting (all isoindole arms)

014 B1g 22.017 21.026 17.094 asymm. stretching (whole molecule)

015 B1g 26.197 25.018 0.939 rocking (whole molecule)

016 Au 28.233 26.962 twisting (whole molecule)

017 B1u 28.405 27.127 7.584 (⊥) wagging (whole molecule)

018 Ag 28.419 27.141 42.435 symm. stretching (whole molecule)

019 B2g 28.681 27.390 5.172 twisting (2 opposite isoindole arms)

020 B3g 30.518 29.145 3.926 twisting (2 opposite isoindole arms)

021 B2u 33.810 32.288 0.598 (k) scissoring (2 opposite isoindole arms) + asymm. stretching (other 2 isoindole arms)

022 B1u 33.954 32.426 2.987 (⊥) twisting (whole molecule)

023 B2g 34.859 33.290 0.003 twisting (whole molecule)

024 B3u 34.859 33.290 10.519 (k) scissoring (2 opposite isoindole arms) + asymm. stretching

5 No. Sym. Energy Infrared Raman Mode assignment calc. corr. intensity intensity

(meV) (km mol−1) (1027 A4 kg−1)

(other 2 isoindole arms)

025 B3g 36.296 34.663 0.343 wagging (2 opposite isoindole arms + aza bridges)

026 B1u 43.783 41.813 4.228 (⊥) wagging (whole molecule)

027 Au 53.911 51.485 twisting (all isoindole arms)

028 B2g 55.032 52.556 0.010 twisting (C2 + H2 vs. C1,3

+ H3 on opposite benzene rings)

029 B3g 55.200 52.716 0.162 twisting (C2 + H2 vs. C1,3

+ H3 on opposite benzene rings)

030 B1u 55.366 52.875 0.005 (⊥) twisting (C2 + H2 vs. C1,3

+ H3 on all benzene rings)

031 B1u 57.103 54.534 15.398 (⊥) wagging (C2 + H2 vs. C1,3

+ H3 on all benzene rings)

032 B1g 60.951 58.208 71.853 scissoring (whole molecule)

033 B2u 61.983 59.194 1.849 (k) scissoring (2 opposite isoindole arms + aza bridges)

034 B3u 62.371 59.564 6.296 (k) scissoring (2 opposite isoindole arms + aza bridges)

035 B3g 63.199 60.355 0.500 twisting (whole molecule)

036 B2g 63.328 60.478 0.335 twisting (whole molecule)

037 Au 66.462 63.472 twisting (whole molecule)

038 Ag 69.518 66.390 13.655 asymm. stretching (whole molecule)

039 B2u 70.548 67.373 0.058 (k) asymm. stretching (whole molecule)

040 B3u 71.382 68.169 3.896 (k) asymm. stretching (whole molecule)

041 Ag 72.517 69.254 40.179 breathing (whole molecule)

042 B1g 73.105 69.815 0.749 rocking (whole molecule)

043 B1g 76.495 73.052 0.046 rocking (whole molecule)

6 No. Sym. Energy Infrared Raman Mode assignment calc. corr. intensity intensity

(meV) (km mol−1) (1027 A4 kg−1)

044 Au 77.897 74.391 wagging (all isoindole arms)

045 B3u 79.593 76.012 24.913 (k) scissoring (whole molecule)

046 B2u 79.840 76.247 4.114 (k) scissoring (whole molecule)

047 B3g 80.019 76.419 0.556 twisting (whole molecule)

048 B2g 80.523 76.899 0.574 twisting (whole molecule)

049 Ag 84.802 80.986 239.222 symm. stretching (4 aza bridges + whole molecule)

050 Au 85.907 82.041 twisting (whole molecule)

051 B1u 87.639 83.696 0.016 (⊥) wagging (whole molecule)

052 B1g 88.198 84.229 5.482 scissoring (whole molecule)

053 B2g 89.114 85.104 8.196 wagging (2 opposite CN − NH HN − CN

groups + H2 + H3)

054 B3g 91.744 87.616 12.670 wagging (2 opposite CN − N − CN

groups + H2 + H3)

055 B1u 92.238 88.087 140.656 (⊥) wagging [all CN − NH (HN ) − CN

groups + H2 + H3]

056 Ag 93.279 89.082 579.725 scissoring (porphyrazine)

057 B3u 93.586 89.374 39.765 (k) rocking + scissoring (whole molecule)

058 B2u 93.798 89.578 45.457 (k) scissoring + breathing (whole molecule)

059 Au 96.288 91.956 twisting (all isoindole arms)

060 B2g 96.547 92.202 1.117 twisting (2 opposite isoindole arms)

061 Ag 96.837 92.480 0.172 breathing (whole molecule)

062 B3g 96.930 92.568 3.416 twisting (2 opposite isoindole arms)

063 Au 96.941 92.578 twisting (all isoindole arms)

064 B2g 98.532 94.098 0.036 twisting (HN ) + wagging (H2 + H3 at 2 opposite benzene rings)

065 B3u 99.193 94.729 1.348 (k) rocking + scissoring (2 opposite

7 No. Sym. Energy Infrared Raman Mode assignment calc. corr. intensity intensity

(meV) (km mol−1) (1027 A4 kg−1)

isoindole arms)

066 B2u 99.232 94.767 0.003 (k) rocking + scissoring (2 opposite isoindole arms)

067 B1u 99.518 95.040 0.378 (⊥) twisting (all H2 + H3)

068 B1u 99.756 95.267 171.781 (⊥) wagging (all H2 + H3 + HN )

069 B3g 99.810 95.319 4.396 twisting (H2 + H3 at 2 opposite benzene rings)

070 Ag 99.906 95.411 71.997 breathing (whole molecule)

071 B2g 102.381 97.773 2.889 twisting (2 opposite CN − NH · · ·

· · · HN − CN groups + H2 + H3)

072 B1g 106.001 101.231 0.600 scissoring (whole molecule)

073 B2u 106.274 101.492 1.906 (k) rocking + scissoring (2 opposite isoindole arms + porphyrazine)

074 B3u 109.505 104.577 53.532 (k) rocking + scissoring (2 opposite isoindole arms + porphyrazine)

075 B1g 111.410 106.397 0.144 rocking + scissoring (2 opposite isoindole arms + porphyrazine)

076 Au 113.568 108.457 twisting (H2 + H3 at 2 opposite benzene rings)

077 B3g 113.578 108.467 0.747 twisting (H2 + H3 at 2 opposite benzene rings)

078 Au 113.807 108.686 twisting (H2 + H3 at 2 opposite benzene rings)

079 B2g 113.821 108.699 1.099 twisting (H2 + H3 at 2 opposite benzene rings)

080 B1u 114.960 109.786 156.957 (⊥) wagging (HN )

081 B3g 123.744 118.175 0.393 twisting (H2 + H3 at 2 opposite

8 No. Sym. Energy Infrared Raman Mode assignment calc. corr. intensity intensity

(meV) (km mol−1) (1027 A4 kg−1)

benzene rings)

082 B1u 123.744 118.175 2.781 (⊥) twisting (H2 + H3 at 2 opposite benzene rings)

083 B2g 124.520 118.917 0.009 twisting (H2 + H3 at 2 opposite benzene rings)

084 B1u 124.524 118.920 2.719 (⊥) twisting (H2 + H3 at 2 opposite benzene rings)

085 B3u 126.960 121.247 305.914 (k) asymm. stretching (CN − N − CN )

+ symm. stretching (H2 at 2 opposite benzene rings) + rocking (2 other benzene rings)

086 Au 127.511 121.773 twisting (H2 + H3 at 2 opposite benzene rings)

087 B2g 127.512 121.774 0.011 twisting (H2 + H3 at 2 opposite benzene rings)

088 Au 128.025 122.264 twisting (H2 + H3 at 2 opposite benzene rings)

089 B3g 128.027 122.266 0.173 twisting (H2 + H3 at 2 opposite benzene rings)

090 Ag 128.052 122.290 151.543 symm. stretching (C2H2 +

C3H3 at all benzene rings)

091 B2u 128.066 122.303 12.066 (k) symm. stretching (C2H2 +

C3H3 at 2 opposite benzene rings)

092 Ag 128.207 122.437 277.445 symm. stretching (C2H2 +

C3H3 at all benzene rings)

093 B3u 128.224 122.454 71.071 (k) symm. stretching (C2H2 +

C3H3 at 2 opposite benzene rings)

9 No. Sym. Energy Infrared Raman Mode assignment calc. corr. intensity intensity

(meV) (km mol−1) (1027 A4 kg−1)

094 B1g 131.435 125.521 147.421 scissoring (whole molecule)

095 B2u 133.998 127.968 16.762 (k) scissoring (2 opposite isoindole arms

+ H2)

096 B3u 134.924 128.852 25.904 (k) scissoring (2 opposite isoindole arms

+ H2)

097 B1g 138.050 131.838 0.362 asymm. stretching [opposite

CN − NH (HN ) − CN groups] + scissoring (whole molecule)

098 B2u 138.225 132.005 195.341 (k) asymm. stretching [opposite

CN − NH (HN ) − CN groups] + scissoring (whole molecule)

099 B1g 139.374 133.103 112.161 scissoring (opposite isoindole arms)

100 B1g 140.969 134.626 222.390 scissoring (opposite isoindole arms)

101 Ag 141.154 134.802 668.426 symm. stretching (all NH HN + N) + breathing (all isoindole arms)

102 B3u 141.747 135.369 71.906 (k) scissoring (all H2 + H3)

103 B2u 142.103 135.708 91.125 (k) scissoring (all H2 + H3

+ NH HN )

104 Ag 145.872 139.308 1290.993 scissoring (all H2 + H3) + breathing (pyrrole rings)

105 B3u 149.337 142.616 8.896 (k) scissoring (all H2 + H3)

106 B2u 149.518 142.790 0.210 (k) symm. stretching (HN ) + scissoring

(H2 + H3 at 2 opposite benzene rings)

107 Ag 149.887 143.142 58.136 scissoring (H2 + H3 at all benzene rings)

108 B1g 150.234 143.473 325.062 scissoring (2 opposite isoindole arms)

10 No. Sym. Energy Infrared Raman Mode assignment calc. corr. intensity intensity

(meV) (km mol−1) (1027 A4 kg−1)

+ asymm. stretching (HN )

109 Ag 150.697 143.916 69.229 scissoring (2 opposite isoindole arms)

+ symm. stretching (HN )

110 B3u 151.125 144.324 0.670 (k) scissoring (H3 at 2 opposite benzene rings)

111 B2u 151.691 144.865 36.690 (k) scissoring (H2 + H3 at 2 opposite benzene rings)

112 B1g 152.730 145.858 38.417 scissoring (H2 + H3 at 2 opposite benzene rings) + asymm. stretching

(NH HN )

113 B1g 157.667 150.572 52.337 scissoring (NH HN )

+ rocking (all H2)

114 B2u 161.655 154.380 117.766 (k) scissoring (2 opposite isoindole arms)

+ asymm. stretching (NH HN )

115 Ag 162.253 154.952 3192.172 symm. stretching (N vs. N)

116 B2u 163.294 155.946 7.469 (k) asymm. stretching (NH HN )

+ rocking (H2)

117 B3u 164.436 157.037 6.547 (k) rocking (H2 at 2 opposite benzene rings) + scissoring (whole molecule)

118 B3u 165.895 158.430 40.839 (k) rocking (H2 + H3 at 2 opposite benzene rings)

119 B1g 166.148 158.671 73.221 rocking (H2 + H3 at 2 opposite benzene rings)

120 B2u 167.744 160.195 34.559 (k) rocking (H2 + H3 at 2 opposite

benzene rings + NH )

121 Ag 168.178 160.610 1610.367 breathing (whole molecule)

122 B1g 168.219 160.649 138.531 rocking (H2 + H3 at 2 opposite

11 No. Sym. Energy Infrared Raman Mode assignment calc. corr. intensity intensity

(meV) (km mol−1) (1027 A4 kg−1)

benzene rings + NH )

123 B3u 169.498 161.871 230.495 (k) scissoring (2 opposite benzene rings)

+ rocking (H2 + H3 at other benzene rings)

124 B2u 171.255 163.548 178.312 (k) scissoring (2 opposite benzene rings)

+ rocking (H2 + H3 at other benzene rings)

125 Ag 171.997 164.257 1348.300 rocking + scissoring (benzene rings)

126 Ag 174.691 166.830 4.866 rocking + scissoring (whole molecule)

127 B3u 178.805 170.759 28.012 (k) scissoring (2 opposite isoindole arms)

128 Ag 182.273 174.071 253.666 scissoring (H2 + H3)

129 B1g 182.498 174.285 271.263 symm. stretching (CN NC

+ NH HN )

130 B2u 183.712 175.445 104.163 (k) scissoring (H2 + H3 at 2 opposite

benzene rings + HN )

131 Ag 184.664 176.354 986.177 scissoring (all benzene rings)

132 B3u 185.996 177.626 58.828 (k) scissoring (2 opposite isoindole arms)

133 B1g 187.907 179.451 31.053 rocking (C3H3 at 2 opposite rings)

134 B3u 187.959 179.501 4.167 (k) rocking (C3H3 at 2 opposite benzene rings)

135 B2u 188.870 180.371 19.224 (k) rocking (C3H3 at 2 opposite benzene rings)

136 B1g 189.028 180.522 57.363 rocking (C3H3 at 2 opposite benzene rings)

137 B3u 189.572 181.041 77.273 (k) symm. stretching (porphyrazine)

138 B2u 190.548 181.974 31.267 (k) symm. stretching (porphyrazine)

12 No. Sym. Energy Infrared Raman Mode assignment calc. corr. intensity intensity

(meV) (km mol−1) (1027 A4 kg−1)

139 Ag 192.239 183.588 885.774 symm. stretching (porphyrazine)

140 B1g 194.886 186.116 30.422 symm. stretching (porphyrazine)

141 B2u 195.774 186.964 4.737 (k) symm. stretching (porphyrazine)

142 Ag 198.168 189.251 10927.901 symm. stretching (porphyrazine) ′ 143 B3u 200.294 191.281 0.044 (k) symm. stretching (C1 vs. C1 ′ + C3 vs. C3 at 2 opposite benzene rings)

′ 144 Ag 200.473 191.452 443.343 symm. stretching (C1 vs. C1 ′ + C3 vs. C3 at 2 opposite benzene rings)

′ 145 B2u 202.040 192.949 2.728 (k) symm. stretching (C1 vs. C1 ′ + C3 vs. C3 at 2 opposite benzene rings)

′ 146 Ag 202.060 192.967 36.441 symm. stretching (C1 vs. C1 ′ + C3 vs. C3 at 2 opposite benzene rings)

147 B1g 204.415 195.216 0.026 stretching (2 opposite bezene rings)

148 B3u 204.454 195.253 9.404 (k) stretching (2 opposite bezene rings)

149 B1g 205.481 196.235 46.882 stretching (2 opposite bezene rings)

150 B2u 205.491 196.244 14.209 (k) stretching (2 opposite bezene rings)

151 B3u 392.791 375.116 8.066 (k) stretching (CH at 2 opposite benzene rings)

152 B1g 392.791 375.116 121.875 stretching (CH at 2 opposite benzene rings)

153 B2u 393.293 375.594 9.875 (k) stretching (CH at 2 opposite benzene rings)

154 B1g 393.293 375.595 134.733 stretching (CH at 2 opposite

13 No. Sym. Energy Infrared Raman Mode assignment calc. corr. intensity intensity

(meV) (km mol−1) (1027 A4 kg−1)

benzene rings)

155 B2u 394.771 377.006 63.935 (k) stretching (CH at 2 opposite benzene rings)

156 Ag 394.775 377.010 376.690 stretching (CH at 2 opposite benzene rings)

157 B3u 395.237 377.452 56.243 (k) stretching (CH at 2 opposite benzene rings)

158 Ag 395.241 377.456 383.928 stretching (CH at 2 opposite benzene rings)

159 B1g 396.711 378.859 108.837 stretching (CH at 2 opposite benzene rings)

160 B3u 396.712 378.860 25.801 (k) stretching (CH at 2 opposite benzene rings)

161 B2u 397.278 379.400 11.317 (k) stretching (CH at 2 opposite benzene rings)

162 B1g 397.278 379.400 108.726 stretching (CH at 2 opposite benzene rings)

163 B2u 397.366 379.485 106.352 (k) stretching (CH at 2 opposite benzene rings)

164 Ag 397.382 379.500 458.288 symm. stretching (CH at 2 opposite benzene rings)

165 B3u 397.862 379.958 83.916 (k) stretching (CH at 2 opposite benzene rings)

166 Ag 397.876 379.972 531.017 symm. stretching (CH at 2 opposite benzene rings)

14 No. Sym. Energy Infrared Raman Mode assignment calc. corr. intensity intensity

(meV) (km mol−1) (1027 A4 kg−1)

167 B3u 439.085 419.326 123.995 (k) asymm. stretching (NH HN )

168 Ag 445.916 425.849 12.611 symm. stretching (NH HN )

Tab. S V. Vibrational modes of free H2Pc grouped according to their symmetry. All calculated vibrational energies were corrected by a factor 0.955 to match experimental data. For infrared- active modes the direction of the oscillating dipole moment is indicated (k: in-plane, ⊥: out-of- plane). The mode assignment identiﬁes oscillating atoms (Fig. S1) and refers to in-plane (out-of- plane) vibrations as stretching, scissoring, rocking, breathing (twisting, wagging).

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