Ernö Pretsch

13C NMR Spectroscopy

The characterization of an organometallic complex involves obtaining a complete understanding of the same right from its identification to the assessment of its purity content, to even elucidation of its stereochemical features. Detailed structural understanding of the organometallic compounds is critical for obtaining an insight on its properties and which is achieved based on the structure-property paradigm.

CARRIER ANTIBIOTICS AND MODEL COMPOUNDS AS COMPONENTS OF SELECTIVE ION-SENSITIVE ELECTRODES

ABSTRACT The ion selectivity exhibited by different types of membrane electrodes is rationalized by a theoretical treatment of the membrane potential. An equation, which is admirably suited for the interpolation of e.m.f.-values, is derived for the electrode response of membrane electrodes of the electrically neutral ligand type (antibiotics, model compounds) to mixed solutions of monovalent and divalent cations. In contrast to the classical Nicolsky equation it describes the contribution of interfering ions to the e.m.f. by an activity-independent selectivity term. Electrically neutral ligands selective for calcium ions to be used as components for liquid membrane electrodes were designed and prepared. The corresponding electrodes are in all respects superior to the calcium ion liquid membrane electrodes described so far.

A Lithium Ion-Selective Electrode Based on a Neutral Carrier

Abstract The performance of a liquid-membrane electrode using a synthetic, neutral carrier in tris-(2-ethyl-hexyl)-phosphate as membrane component in a PVC matrix is described. Selectivities, working range and lifetime are discussed. The electrode makes possible the measurement of lithium ion activities in the range 1M to 10−5M. The selectivities of lithium over sodium, potassium, magnesium and calcium are 20, 140, 6,000, and 1,900 respectively.

UV/Vis Spectroscopy

∆ E = hν (photon) = h(c/λ) = hcν ! = E (LUMO) − E (HOMO) Examples: π-to-π* n-to-π* d-to-d (transition metals) 1. What transition(s) is(are) expected in the following molecules between the HOMO and LUMO? 2. Use the information on the next page on d-to-d transitions and the information given below to identify the solutions labeled 1 to 6.