README.TXT The enclosed disk contains the file SUPMAT.DOC, in which all the analysed transition frequencies of 1,1,1,2-Tetrafluoroethane (HFC 134a) are listed. The SUPMAT.DOC file is readable using MS-Word 6 for Windows 3.11. Two Tables are included in SUPMAT.DOC. Table I contains the ground state transition frequencies, and Table II contains the torsional state lines. The first page of SUPMAT.DOC is explanatory. All the reported millimetre-wave measurements are original, while the centimetre-wave transition frequencies were taken from the following previous works: 1. L.-H. Xu, A.M. Andrews, R.R. Cavanagh, G.T. Fraser, K.K. Irikura, F.J. Lovas, J.-U. Grabow, W. Stahl, M.K. Crawford, and R.J. Smalley. J. Phys. Chem. A 101, 2288-2297 (1997). 2. T. Ogata, and Y. Miki J. Mol. Struct. 140, 49-56 (1986).