Supporting Information

© Copyright Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, 2007

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Hypervalent Silicon versus Carbon: Ball-in-a-Box Model

Simon C. A. H. Pierrefixe, Célia Fonseca Guerra and F. Matthias Bickelhaupt*[a]

[a] Theoretische Chemie, Scheikundig Laboratorium der Vrije Universiteit, De Boelelaan 1083, NL-1081 HV

Amsterdam, The Netherlands. Fax: +31 - 20 - 59 87 629. E-mail: FM.Bickelhaupt@few.vu.nl

[**] We thank the Netherlands Organization for Scientific Research (NWO-CW) and the National Research School

Combination for Catalysis (NRSC-C) for financial support.

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Contents

Figure S1. Schematic MO interaction diagram describing: (a) the interaction between central

atom A•••• and the axial substituents Cl2–• in Cl–A–Cl–•••; and (b) the interaction between Cl–A–

Cl–••• and the equatorial substituents H3••• in D3h symmetric Cl–AH3–Cl– (for the construction of

H3••• and Cl2–•, see Figure S4).

Figure S2. Schematic MO interaction diagram describing: (a) the interaction between central

atom A•••• and the equatorial substituents H3••• in AH3

•; and (b) the interaction between AH3• and

the axial substituents Cl2–• in D3h symmetric Cl–AH3–Cl– (for the construction of H3••• and Cl2–•,

see Figure S4).

Figure S3. Schematic MO interaction diagram describing: (a) the interaction between the

equatorial substituents H3••• and the axial substituents Cl2–• in the "box" Cl-H3-Cl–••••; and (b) the

interaction between the central atom A•••• and the "box" Cl-H3-Cl–•••• in D3h symmetric Cl–AH3–

Cl– (for the construction of H3••• and Cl2–•, see Figure S4).

Figure S4. Schematic MO interaction diagram describing: (a) the interaction between Cl– and Cl•

in Cl2–•; and (b) the interaction between three hydrogen atoms in H3•••.

Figure S5. Contour plots of the singly-occupied carbon 2pz and silicon 3pz AOs in between the

chlorine 3pz lobes of the a2'' SOMO of the "box" of substituents Cl-H3-Cl–•••• in the geometry of

transition state 1a and transition complex 2a, respectively.

Table S1. Cartesian coordinates, point-group symmetry and total energy relative to ADF's basic

atoms of species occurring in this study, optimized at BP86/TZ2P.

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1a'1

1e'

1a"2

2a"2

2a'1

A• • • • Cl-A-Cl – • • • Cl2– •

Cl-A-Cl – • • •

2a'1

2a"2

2e'

3a'1

1a'1

1e'

H3• • •Cl-AH3-Cl –

a

b

Figure S1. Schematic MO interaction diagram describing: (a) the interaction between central

atom A•••• and the axial substituents Cl2–• in Cl–A–Cl–•••; and (b) the interaction between Cl–A–

Cl–••• and the equatorial substituents H3••• in D3h symmetric Cl–AH3–Cl– (for the construction of

H3••• and Cl2–•, see Figure S4).

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a

b

AH3•

2a"2

2a'1

Cl2- •AH3•

1a'1

1e'

1a"2

1a'1

1e'

1a"2

A• • • •

1a'1

1e'

H3• • •

Cl-AH3-Cl –

Figure S2. Schematic MO interaction diagram describing: (a) the interaction between central

atom A•••• and the equatorial substituents H3••• in AH3

•; and (b) the interaction between AH3• and

the axial substituents Cl2–• in D3h symmetric Cl–AH3–Cl– (for the construction of H3••• and Cl2–•,

see Figure S4).

S5

a

b

Cl-H3-Cl – • • • •

1a'1

1e'

H3• • •

2a"2

2a'1

Cl2- •

1a'1

1e'

1a"2

A• • • • Cl-H3-Cl – • • • •Cl-AH3-Cl –

2a'1

2a"2

3a'1

2e'

Figure S3. Schematic MO interaction diagram describing: (a) the interaction between the

equatorial substituents H3••• and the axial substituents Cl2–• in the "box" Cl-H3-Cl–••••; and (b) the

interaction between the central atom A•••• and the "box" Cl-H3-Cl–•••• in D3h symmetric Cl–AH3–

Cl– (for the construction of H3••• and Cl2–•, see Figure S4).

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a

b

Cl2- •Cl– Cl•

1a'1

1e'

H3• • •3H•

1s

3pz 3pz

Figure S4. Schematic MO interaction diagram describing: (a) the interaction between Cl– and Cl•

in Cl2–•; and (b) the interaction between three hydrogen atoms in H3•••.

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C

Si

Figure S5. Contour plots of the singly-occupied carbon 2pz (upper, in blue) and silicon 3pz AOs

(lower, in red) in between the chlorine 3pz lobes (in black) of the a2'' SOMO of the "box" of

substituents Cl-H3-Cl–•••• in the geometry of transition state 1a and transition complex 2a,

respectively, computed at BP86/TZ2P (scan values: ±0.04 ±0.10, ±0.20, ±0.40, ±1.00).

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Table S1. Cartesian coordinates (in Å), point-group symmetry and total energy relative to ADF's

basic atoms of species occurring in this study, optimized at BP86/TZ2P.

1a ClCH3Cl– (D3h) –604.32 kcal mol-1

C 0.000000 0.000000 0.000000

H 1.076774 0.000000 0.000000

H -0.538387 0.932514 0.000000

H -0.538387 -0.932514 0.000000

Cl 0.000000 0.000000 2.351619

Cl 0.000000 0.000000 -2.351619

1b ClCH3Cl– (C3v) –609.98 kcal mol-1

C 0.000000 0.000000 0.086849

H 1.037037 0.000000 -0.243161

H -0.518519 0.898101 -0.243161

H -0.518519 -0.898101 -0.243161

Cl 0.000000 0.000000 1.958848

Cl 0.000000 0.000000 -2.984919

1c ClCH3 (C3v) –508.72 kcal mol-1

C 0.000000 0.000000 0.391901

H 1.038060 0.000000 0.049306

H -0.519030 0.898986 0.049306

H -0.519030 -0.898986 0.049306

Cl 0.000000 0.000000 2.193959

2a ClSiH3Cl– (D3h) –546.38 kcal mol-1

Si 0.000000 0.000000 0.000000

H 1.486500 0.000000 0.000000

H -0.743250 1.287346 0.000000

H -0.743250 -1.287346 0.000000

Cl 0.000000 0.000000 2.359219

Cl 0.000000 0.000000 -2.359219

2b ClSiH3Cl– (C3v) –537.80 kcal mol-1

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Si 0.000000 0.000000 0.000000

H 1.457288 0.000000 0.270812

H -0.728644 1.262049 0.270812

H -0.728644 -1.262049 0.270812

Cl 0.000000 0.000000 3.079400

Cl 0.000000 0.000000 -2.196680

2c ClSiH3 (C3v) –427.34 kcal mol-1

Si 0.000000 0.000000 0.159517

H 1.412122 0.000000 -0.316888

H -0.706061 1.222934 -0.316888

H -0.706061 -1.222934 -0.316888

Cl 0.000000 0.000000 2.232485

3a ClCCl–••• (D8 h) –227.07 kcal mol-1

C 0.000000 0.000000 0.000000

Cl 0.000000 0.000000 1.978398

Cl 0.000000 0.000000 -1.978398

4a ClSiCl–••• (D8 h) –214.29 kcal mol-1

Si 0.000000 0.000000 0.000000

Cl 0.000000 0.000000 2.280416

Cl 0.000000 0.000000 -2.280416

5a ClCHCl–•• (C2v) –351.73 kcal mol-1

C 0.000000 0.000000 -0.419287

H 0.000000 0.000000 -1.520962

Cl 1.992655 0.000000 0.071977

Cl -1.992655 0.000000 0.071977

5b ClCHCl–•• (Cs) –352.23 kcal mol-1

C 0.463561 -0.197935 0.000000

H 1.563412 -0.227810 0.000000

Cl -0.100876 1.555546 0.000000

Cl -0.059494 -2.484332 0.000000

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6a ClCH2Cl–• (C2v) –475.69 kcal mol-1

H 0.000000 0.926867 0.317901

C 0.000000 0.000000 -0.253723

H 0.000000 -0.926867 0.317901

Cl 2.091496 0.000000 -0.773183

Cl -2.091496 0.000000 -0.773183

6b ClCH2Cl–• (Cs) –480.87 kcal mol-1

H -0.017463 -0.191783 -0.939721

C -0.555694 -0.104562 0.000000

H -0.017463 -0.191783 0.939721

Cl 2.546982 -0.929859 0.000000

Cl -2.217219 -0.657191 0.000000

7 ClH3Cl–•••• (D3h) –190.74 kcal mol-1

H 1.076774 0.000000 0.000000

H -0.538387 0.932514 0.000000

H -0.538387 -0.932514 0.000000

Cl 0.000000 0.000000 2.406949

Cl 0.000000 0.000000 -2.406949

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8 ClH3Cl–•••• (D3h) –199.95 kcal mol-1

H 1.486500 0.000000 0.000000

H -0.743250 1.287346 0.000000

H -0.743250 -1.287346 0.000000

Cl 0.000000 0.000000 2.316638

Cl 0.000000 0.000000 -2.316638

FCH3F– (D3h) –653.16 kcal mol-1

C 0.000000 0.000000 0.000000

H 1.078093 0.000000 0.000000

H -0.539046 0.933656 0.000000

H -0.539046 -0.933656 0.000000

F 0.000000 0.000000 1.853834

F 0.000000 0.000000 -1.853834

FCF–••• (D8 h) –271.77 kcal mol-1

C 0.000000 0.000000 0.000000

F 0.000000 0.000000 1.593734

F 0.000000 0.000000 -1.593734

FSiH3F– (D3h) –546.38 kcal mol-1

Si 0.000000 0.000000 0.000000

H 1.516142 0.000000 0.000000

H -0.758071 1.313018 0.000000

H -0.758071 -1.313018 0.000000

F 0.000000 0.000000 1.757848

F 0.000000 0.000000 -1.757848

FSiF–••• (D8 h) –286.72 kcal mol-1

Si 0.000000 0.000000 0.000000

F 0.000000 0.000000 1.740159

F 0.000000 0.000000 -1.740159

ClGeH3Cl– (D3h) –510.78 kcal mol-1

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Ge 0.000000 0.000000 0.000000

H 1.523943 0.000000 0.000000

H -0.761972 1.319774 0.000000

H -0.761972 -1.319774 0.000000

Cl 0.000000 0.000000 2.492745

Cl 0.000000 0.000000 -2.492745

ClGeCl–••• (D8 h) –195.58 kcal mol-1

Ge 0.000000 0.000000 0.000000

Cl 0.000000 0.000000 2.404837

Cl 0.000000 0.000000 -2.404837

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ClSnH3Cl– (D3h) –490.25 kcal mol-1

Sn 0.000000 0.000000 0.000000

H 1.713262 0.000000 0.000000

H -0.856631 1.483728 0.000000

H -0.856631 -1.483728 0.000000

Cl 0.000000 0.000000 2.620764

Cl 0.000000 0.000000 -2.620764

ClSnCl–••• (D8 h) –192.52 kcal mol-1

Sn 0.000000 0.000000 0.000000

Cl 0.000000 0.000000 2.575805

Cl 0.000000 0.000000 -2.575805

ClPbH3Cl– (D3h) –456.22 kcal mol-1

Pb 0.000000 0.000000 0.000000

H 1.764769 0.000000 0.000000

H -0.882385 1.528335 0.000000

H -0.882385 -1.528335 0.000000

Cl 0.000000 0.000000 2.734612

Cl 0.000000 0.000000 -2.734612

ClPbCl–••• (D8 h) –178.91 kcal mol-1

Pb 0.000000 0.000000 0.000000

Cl 0.000000 0.000000 2.718438

Cl 0.000000 0.000000 -2.718438

Cl– –90.28 kcal mol-1

Cl 0.000000 0.000000 0.000000

F– –92.94 kcal mol-1

F 0.000000 0.000000 0.000000

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