The Si-doped planar tetracoordinate carbon (ptc) unit CAl 3 Si could be used as a building block or inorganic ligand during cluster-assembly Supporting Information. Li-ming Yang, Yi-hong Ding*, Chia-chung Sun State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 130023, People s Republic of China (E-mail: yhdd@mail.jlu.edu.cn; Fax: +86-431-8498026) Full citations for ref 81: 81. Gaussian03 (RevisionA.1), M. J. Frisch, G. W. Trucks, H. B. Schlegel, G. E. Scuseria, M. A. Robb, J. R. Cheeseman, J. A. Montgomery, Jr., T. Vreven, K. N. Kudin, J. C. Burant, J. M. Millam, S. S. Iyengar, J. Tomasi, V. Barone, B. Mennucci, M. Cossi, G. Scalmani, N. Rega, G. A. Petersson, H. Nakatsuji, M. Hada, M. Ehara, K. Toyota, R. Fukuda, J. Hasegawa, M. Ishida, T. Nakajima, Y. Honda,O. Kitao, H. Nakai, M. Klene, X. Li, J. E. Knox, H. P. Hratchian, J. B. Cross, C. Adamo, J. Jaramillo, R. Gomperts, R. E. Stratmann, O. Yazyev, A. J. Austin, R. Cammi, C. Pomelli, J. W. Ochterski, P. Y. Ayala, K. Morokuma, G. A. Voth, P. Salvador, J. J. Dannenberg, V. G. Zakrzewski, S. Dapprich, A. D. Daniels, M. C. Strain, O. Farkas, D. K. Malick, A. D. Rabuck, K. Raghavachari, J. B. Foresman, J. V. Ortiz, Q. Cui, A. G. Baboul, S. Clifford, J. Cioslowski, B. B. Stefanov, G. Liu, A. Liashenko, P. Piskorz, I. Komaromi, R. L. Martin, D. J. Fox, T. Keith, M. A. Al-Laham, C. Y. Peng, A. Nanayakkara, M. Challacombe, P. M.W. Gill, B. Johnson, W. Chen, M.W. Wong, C. Gonzalez, J. A. Pople, Gaussian, Inc., Pittsburgh, PA, 2003. Some references on ptc and related species are listed as follows: 11. (a) Collins, J. B.; Dill, J. D.; Jemmis, E. D.; Apeloig, Y.; Schleyer, P. v. R.; Seeger, R.; Pople, J. A. J. Am. Chem. Soc. 1976, 98, 5419. (b) Cotton, F. A.; Millar, M. J. Am. Chem. Soc. 1977, 99, 7886. (c)erker, G.; Wicher, J.; Engel, K.; Resenfeldt, F.; Dietrich, W.; Kruger, C. J. Am. Chem. Soc. 1980, 102, 6344. (d) Keese, R. Nachr. Chem. Tech. Lab. 1982, 30, 844. (e) Stahl, D.; Maquin, F.; Gaumann, T.; Schwarz, H.; Carrupt, P.-A.; Vogel, P. J. Am. Chem. Soc. 1985, 107, 5049. (f)mcgrath, M. P.; Radom, L. J. Am. Chem. Soc. 1992, 114, 8531. (g) Luef, W.; Keese, R. Adv. Strain. Org. Chem. 1993, 3, 229. (h) Rottger, D.; Erker, G.; Frohlich, R.;
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Note1. An imaginary frequency indicates the existence of a vibrational mode that is dynamically unstable and leads to a more stable structure. Transition states of a chemical reaction are saddle points exhibiting only one imaginary frequency. Saddle points with more dynamical systems with sufficiently high vibrational energy but are generally not of chemical significance. In this report, NIMAG means the number of imaginary frequency of saddle point. [Note1] m N q : m means spin electron state (singlet, triplet), N means the sequence number of various isomers, superscript q means the charge of the total system. Figure 1 Schematic energy profile for singlet 1 [C 2 Si 2 Al 6 M] q : a) (M,q)=(Li,1); b) (M,q)=(Na,1); c) (M,q)=(K,1); d) (M,q)=(Be,0); e) (M,q)=(Mg,0); f) (M,q)=(Ca,0) calculated at the B3LYP/6-311+G(d) level. Energy values are in kcal/mol. NIMAG means the number of imaginary frequency of saddle point. m N q : m means spin electron state, N represents the sequence number of various isomers, superscript q means the charge of the total system. For simplicity, the notations Ho-Li, Ho-Na Ho-K Ho-Be Ho-Mg and Ho-Ca for isomers are omitted.
1 1 (s-s-90-1) 1 1 (s-s-90-2) 1.81 1 1 (s-s-90-3) 3.64 1 1 (s-c-90-3) 5.10 1 1 (s-s-0-1) 1.63 1 1 (s-s-0-2) 1.66 1 1 (s-s-0-3) 5.83 1 1 (s-c-0-1) 2.92 1 1 (s-c-0-2) 2.94 1 1 (s-c-0-3) 4.80 1 1 (s-c-0-4) 4.85 1 1 (c-c-90-1) 4.95 1 1 (c-c-90-2) 8.21 1 1 (c-c-0-1) 5.14 1 1 (c-c-0-2) 6.17 1 1 (c-c-0-3) 7.22 1 1 (c-c-0-4) (NIMAG=2) 9.69 1 1 (c-c-0-5) (NIMAG=3) 12.50 1 1 (c-c-90-3) (NIMAG=2) 11.77 1 1 (f-f-0-1) 11.90 1 2-15.20 1 3-13.78 1 4-13.78 1 5-7.65 1 6-3.90 1 7-2.65
1 8-2.42 1 9-1.66 1 10-1.54 1 11-0.54 1 12-0.26 1 13-0.12 1 14 0.04 1 15 0.10 1 16 0.15 1 17 1.24 1 18 1.37 1 19 1.48 1 20 1.49 1 21 1.56 1 22 1.77 1 23 2.38 1 24 2.59 1 25 3.77 1 26 4.38 1 27 5.58 1 28 1 29 7.89 8.28 a) 1 [C 2 Si 2 Al 6 Li] 1 30 12.12 1 31 (s-c-0-1) 10.67
1 1 (s-s-90-1) 1 1 (s-s-90-2) 0.76 1 1 (s-s-90-3) 1.54 1 1 (c-c-90) 5.83 1 1 (f-f-0) 14.05 1 1 (s-s-0) 2.72 1 1 (s-c-0) 2.11 1 1 (c-c-0) 3.99 1 1 (s-c-90) 5.88 1 1 (c-c-0-5) (NIMAG=2) 8.81 1 1 (c-c-90-1) (NIMAG=2) 11.55 1 1 (c-c-0-1) (NIMAG=3) 11.92 1 2-9.62 1 3-5.01 1 4-1.66 1 5 0.29 1 6 0.77 1 7 1.89 1 8 2.13 1 9 6.02 1 10 9.99 1 11 16.26 b) 1 [C 2 Si 2 Al 6 Na]
1 1 (s-s-90-1) 1 1 (s-s-90-2) 0.20 1 1 (s-s-0) 0.50 1 1 (s-s-0) 0.83 1 1 (s-s-0) 0.83 1 1 (s-c-90) 3.97 1 1 (c-c-0-2) (NIMAG=3) 6.03 1 1 (c-c-0-5) (NIMAG=3) 7.33 1 1 (c-c-90-1) (NIMAG=2) 8.48 1 1 (f-f-0) 11.58 1 2-12.66 1 3-10.58 1 4 0.56 1 5 6.33 1 6 11.30 1 7 17.58 c) 1 [C 2 Si 2 Al 6 K]
1 1(s-s-90-1) 8.35 12.38 16.03 1 1(s-c-0) 11.25 1 1(s-c-0) 11.35 1 1(s-c-0) 15.00 1 1(s-c-0) 15.07 1 1(s-c-90-1) 15.10 1 1(s-c-90-2) 18.16 1 1(c-c-0-2) (NIMAG=3) 29.98 1 1(c-c-0-5) (NIMAG=3) 35.94 1 1(c-c-90-1) (NIMAG=2) 37.47 1 1(c-c-0-1) (NIMAG=7) 111.51 1 2-28.93 1 3-28.78 1 4-27.94 1 5-27.24 1 6-25.19 1 7-23.86 1 8-19.06 1 9-18.65 1 10-17.36 1 11-17.30 1 12-16.43 1 13-16.42 1 14-16.23 1 15-16.11 1 16-15.95 1 17-15.29 1 18-14.04 1 19-13.71 1 20-8.07 1 21-6.00 1 22-6.00 1 23-0.58 1 24 2.90 d) 1 [C 2 Si 2 Al 6 Be]
1 1(s-s-90-1) 1 1(s-s-90-2) 1 1(s-s-90-3) 0.91 1.85 2.79 2.79 4.39 6.11 6.17 1 1(c-c-0-2) (NIMAG=3) 24.91 1 1(c-c-0-5) (NIMAG=3) 32.75 1 1(c-c-90-1) (NIMAG=2) 40.47 1 2-10.83 1 3-2.71 1 4-0.94 1 5-0.34 1 6 2.20 1 7 2.25 1 8 4.60 1 9 4.65 1 10 5.57 1 11 6.13 1 12 6.27 1 13 10.28 1 14 12.46 1 15 13.28 1 16 13.75 e) 1 [C 2 Si 2 Al 6 Mg]
1 1(s-s-90-1) 1 1(s-s-90-2) 0.08 1.38 1.39 1.39 1.42 1.66 1.67 1 1(c-c-0-2) (NIMAG=3) 26.37 1 1(c-c-0-5) (NIMAG=3) 27.93 1 1(c-c-90-1) (NIMAG=2) 29.33 1 2-25.95 1 3-19.29 1 4-16.52 1 5-13.51 1 6-10.71 1 7-8.79 1 8-8.78 1 9-5.32 1 10-2.10 1 11-1.11 f) 1 [C 2 Si 2 Al 6 Ca]
Figure 2 Most relevant species of [C 2 Si 2 Al 6 M 2 ] (M=Li, Na, K) at the B3LYP/6-311+G(d) level. Energy values are in kcal/mol. NIMAG means the number of imaginary frequency of saddle point. m N q : m means spin electron state, N represents the sequence number of various isomers, superscript q means the charge of the total system. "f-f" stands for face-to-face sandwich form, "f-s" stands for face-to-side sandwich form, "f-c" stands for face-to-corner sandwich form. For simplicity, the notations Ho-Li, Ho-Na Ho-K for isomers are omitted, and we only listed the sandwich-like and low-lying isomers, all the other isomers are found in SI. 1 1(s-s-0-1) 1 1(s-s-0-2) 0.70 1 1(s-s-0-3) 0.79 1 1(s-s-0-4) 1.14 1 1(s-s-0-5) 1.24 1 1(s-s-0-6) 1.32 1 1(s-s-0-7) 5.00 1 1(s-c-90-1) 18.06 1 1(s-c-90-2) 18.58 1 1(s-c-0) 17.78 1 1(s-c-0) 19.30 1 1(s-c-0) 23.84 1 1(s-c-0) 24.51 18.79 18.81 1 1(s-c-0) 17.31 1 1(s-c-0) 17.81 19.20 20.17 18.47 1 1(c-c-90-1) (NIMAG=4) 35.89 1 1(c-c-0-2) (NIMAG=3) 37.01 1 1(c-c-90-1) (NIMAG=4) 38.70
1 2-13.94 1 3-11.48 1 4-10.33 1 5-10.32 1 6-9.79 1 7-9.49 1 8-8.45 1 9-7.99 1 10-7.51 1 11-7.15 1 12-6.81 1 13-6.57 1 14-5.78 1 15-5.51 1 16-3.49 1 17-2.08 1 18 1.52 1 20 2.93 1 21 3.70 1 22 7.85 1 23 10.01 1 24 10.20 a) 1 C 2 Si 2 Al 6 Li 2
1 1(s-s-0-1) 1 1(s-s-0-2) 0.06 1 1(s-s-0-4) 0.42 1 1(s-s-0-6) 0.43 1 1(s-s-0-3) 0.97 1 1(s-s-0-5) 1.68 1 1(s-c-0) 14.51 1 1(c-c-0-1) (NIMAG=4) 29.61 1 1(c-c-0-2) (NIMAG=3) 32.33 1 2-10.93 1 3-8.75 1 4-7.59 1 5-3.24 1 6-2.29 1 7-0.91 1 8-0.42 1 9 3.69 1 10 5.93 1 11 10.06 1 12 11.09 1 13 20.66 b) 1 [C 2 Si 2 Al 6 Na 2 ] 1 14 23.15
1 1(s-s-0-1) 1 1(s-s-0-2) 0.46 1 1(s-s-0-4) 0.13 1 1(s-s-0-6) 0.19 1 1(s-s-0-3) 0.84 1 1(s-s-0-5) 11.72 1 1(c-c-0-1) (NIMAG=4) 24.59 1 1(c-c-0-1) (NIMAG=4) 25.44 1 1(c-c-0-1) (NIMAG=4) 26.16 1 2-16.04 1 3-12.09 1 4-7.91 1 5-7.32 1 6-4.51 1 7-3.85 1 8-2.93 1 9 2 1 10 20.70 c) 1 [C 2 Si 2 Al 6 K 2 ]
Figure 3. Schematic energy profile for singlet hetero-decked compounds 1 [CpM(CAl 3 Si)] q : a) (M,q)=(Li,1); b) (M,q)=(Na,1); c) (M,q)=(K,1); d) (M,q)=(Be,0); e) (M,q)=(Mg,0); f) (M,q)=(Ca,0) calculated at the B3LYP/6-311+G(d) level. Energy values are in kcal/mol. "f-f" stands for face-to-face sandwich form, "f-s" stands for face-to-side sandwich form, "f-c" stands for face-to-corner sandwich form. For simplicity, the notations Het-Li, Het-Na Het-K Het-Be Het-Mg and Het-Ca for isomers are omitted. 1 1(f-c-1) 1 1(f-s) 1 1(f-c-2) 1 1(f-f) 1 2 1 3 0.16 0.44 1.45 17.91 18.37 1 4 1 5 1 6 1 7 1 8 1 9 21.09 21.73 21.79 23.79 25.85 26.37 1 10 34.70 1 11 38.57 1 12 39.63 1 13 39.63 1 14 42.31
1 15 1 16 1 17 1 18 1 19 43.82 44.89 45.46 46.54 48.53 1 20 1 21 1 22 1 23 53.52 56.06 56.27 64.30 1 24 69.51 1 25 1 26 73.91 98.03 a) 1 [CpLi(CAl 3 Si)] 1 27 99.18
1 1(f-s) 1 1(f-c) 0.66 1 1(f-c) 1.30 1 1(f-f) 4.65 19.80 20.45 22.13 22.50 22.68 22.73 24.26 25.29 27.89 31.50 31.85 34.44 35.15 44.77 48.17 b) 1 [CpNa(CAl 3 Si)]
1 1(f-s-1) 1 1(f-s-1) 0.37 1 1(f-f) 4.45 1 2 20.04 1 3 1 4 21.32 22.28 c) 1 [CpK(CAl 3 Si)] 1 5 23.72
1 1(f-c) 1 1(f-f) 0.27 1 1(f-s) 2.17 6.83 8.94 11.74 16.33 18.08 18.99 19.59 20.08 20.72 21.38 24.98 26.93 29.08 37.55 37.69 38.91 38.98 39.06 39.86 41.51 42.84 43.53 45.21 45.79 46.29
47.71 52.13 52.64 54.19 54.84 55.26 55.54 56.35 61.59 62.43 67.03 67.40 69.11 72.25 72.44 72.83 74.92 77.67 80.27 80.86 87.38 96.83 100.38 107.70 133.08 d) 1 [CpBe(CAl 3 Si)]
1 1(f-s-1) 1 1(f-s-1) 1.62 1 1(f-f) 11.10 14.86 14.97 16.21 17.32 25.54 24.70 26.22 e) 1 [CpMg(CAl 3 Si)] 1 1(f-s-1) 1 1(f-s-1) 0.03 1 1(f-f) 8.36 1 2 11.79 1 3 12.24 1 4 16.88 1 5 30.67 1 6 41.64 1 7 45.46 f) 1 [CpCa(CAl 3 Si)]
Figure 3. Schematic energy profile for singlet saturated hetero-decked compounds 1 (Li) + [CpM(CAl 3 Si)] (M=Li, Na, K) calculated at the B3LYP/6-311+G(d) level. Energy values are in kcal/mol. For simplicity, the notations Het-Li, Het-Na Het-K for isomers are omitted. 0.43 1.16 1.16 1.32 2.60 14.33 14.84 15.46 15.54 0.05 1.61 1.71 2.22 5.09 5.40 7.18 7.94 8.09 8.60 8.76 9.11 9.15 9.67 26.85 27.90
1.18 2.65 3.16 3.67 7.33
Figure 3. Various extend species were designed and obtained as energy minima, they were calculated at the B3LYP/6-311+G(d) level. Energy values are in kcal/mol. Fig 3 display extend species of alkali-metal: [CpM(CAl 3 Si)MCp] q (M=Li, Na, K, q=+1; M=Be, Mg, Ca, q=-1). 0.13 0.28 0.75 0.79 0.84 0.88