1. Location of transition states in reaction mechanisms
2. Determination of molecular symmetries by force field calculations and evaluation of symmetric and nonsymmetric conformational transition states avoiding complete point-by-point mapping
3. Thermal unimolecular decomposition of β-propiolactone (oxetan-2-one)
4. Thermal unimolecular decomposition of β-butyrolactone (4-methyloxetan-2-one)
5. Frisch, M.J., Trucks, G.W., Schlegel, H.B., Scuseria, G.E., Robb, M.A., Cheeseman, J.R., Zakrazewski, V.G., Montgomery, J.A., Startmann, R.E., Burant, J.C., Dapprich, S., Millam, J.M., Daniels, A.D., Kudin, K.N., Strain, M.C., Farkas, O., Tomasi, J., Barone, V., Cossi, M., Cammi, R., Mennucci, B., Adamo, C., Clifford, S., Ochterski, J., Petersson, G.A., Ayala, P.Y., Cui, Q., Morokuma, K., Malik, D.K., Rabuck, A.D., Raghavachar, K., Foresman, J.B., Cioslowski, J., Ortiz, J.V., Stefanov, B.B., Liu, G., Liashenko, A., Piskorz, P., Komaromi, I., Gomperts, R., Martin, R.L., Fox, D.J., Keith, T., Al-Laham, M.A., Peng, C.Y., Nanyakkara, A., Gonzalez, C., Challacombe, M., Gill, P.M.W., Johnson, B., Chen, W., Wong, M.W., Andres, J.L., Head-Gordon, M., Replogle, E.S., Pople, J.A., 1998. gaussian 98 (Revision A.3) Gaussian Inc., Pittsburgh, PA, USA.