Hydrogenic ions, spectral properties

The above characteristics make these systems very promising for radiation effect studies and in particular for metrological applications such as the measurement of the Rydberg constant directly in frequency units. One can indeed expect very narrow resonances between circular states, with spectral lines only quadratically sensitive to stray electric fields and frequencies depending only slightly upon the atomic ion core properties and being easily related to the hydrogen frequencies via the determination of very small quantum defects corrections. 

The dodecahydrododecaborate anion, B H 2-, is termed unique with considerable justification. This ion and its perhalo derivatives, e.g., Bi2C1i22-, are the most symmetrical molecular aggregates known. The boron atoms occupy the vertices of a regular icosahedron and each is bonded terminally to a hydrogen atom all boron atoms are environmentally equivalent.7,8 This anion is the only known example of the 7 symmetry group.8 General spectral, physical, and chemical properties of Bx2Hi22-are detailed in a paper by Muetterties et al.9... 

Decacarbonyl- -hydrido-/i-[(triethylphosphine)gold]triosmium has similar properties and spectral characteristics. IR (hexane cm ) 2089(m), 2045(s), 2039(m), 2008(s), 1995(s), 1978(s), and 1943(vw). The HNMR spectrum (250 MHz, chloroform-d, 5 parts per million downfield from TMS, ambient temperature) shows a doublet of triplets (J= 19 and 9 Hz) at 1.15 resulting from the methyl hydrogen atoms, a multiplet at 1.85 for the methylene protons, and a sharp hydride singlet at — 11.84. Low resolution mass spectra of this compound contain a peak at m/z = 1172 corresponding to the molecular ion ( Os, Au). 

---