Multiconfiguration relativistic Dirac-Fock (MCDF) values have been computed for the first four ionization potentials (IPs) of element 104 (unnilquadium) and of the other group 4 elements (Ti, Zr, and Hf). Factors were calculated that allowed correction ofthe systematic errors between the MCDF IPs and the experimental IPs. Single "experimental" IPs evaluated in eV (to ± 0.1 eV) for element 104 are: [

The Raman crystal spectra of KTcO4, KReO4, Na2MoO4, Na2WO4, Na2MoO4·2H2O, and Na2WO4·2H2O, and the Raman aqueous spectra of TcO4— and MoO42— have been observed. Infrared spectra of Nujol mulls of all the salts were measured in the rock salt region. Infrared spectra in the CsBr region were also obtained for Na2MoO4 and Na2WO4. For the tetrahedral ions (Td symmetry) of the latter two salts v2(e)>v4(f2), which represents an inversion of the usual order. Examination of all the spectra leads to the conclusion that the Raman spectrum of aqueous pertechnetate ion, which shows only two lines, represents the spectrum of tetrahedral TcO4— ion perturbed by the close association of water molecules. The appearance of two instead of four Raman lines in the spectrum is shown to result from the accidental degeneracy of v1(a1) and v3(f2) vibrations. The v2(e) line is not detected probably because of its low intensity and broadness. The observation of three rather than the expected four Raman lines for molybdate ion is similarly believed to be due to the low intensity and broadness of the v2(e) line. This explanation is also offered as an alternative explanation for the absence of the fourth line in the Raman spectrum of ReO4—(aq) and WO42—(aq) to that previously given, namely, that v2(e) and v4(f2) are sufficiently close together that they are unresolved.

The Raman spectra of K2NbOF8• H20 dissolved in water and K2NbF7 dissolved in 1 to 50% HF are compared with the Raman spectra of crystalline (which also can be considered as K2Nb(OH)2F6), CsNbFe, and K2NbF7 to show that the NbOF62~(or Nb(OH)2F52-) and NbF8~ions are present in these solutions. The Raman lines characteristic of the NbF72~ion were not seen in any of the solutions. The infrared spectrum of K2Nb0F5-H20 was recorded from 650 to 4000 cm,-1 to gain information on whether the NbOF52_ or Nb(OH)2F62-ion is present in the crystals and the solutions. The infrared and Raman spectra are found to be consistent with the presence of NbOF52-ions in the crystals, but they are not found to be consistent with the presence of Nb(OH)2F52_ ions.

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