Neodymium spectroscopy

Diorganotin(IV) complexes with 4//-pyrido[l,2-n]pyrimidin-4-ones 109 (96MI4), complexes of 2-methyl- and 2-methyl-8-nitro-9-hydroxy-4//-pyrido[l,2-n]pyrimidin-4-ones with Ag(I), Cu(II), Ni(II), Co(II), and Mn(II) ions (00MI23), 2,4-dimethyl-9-hydroxypyrido[l, 2-n]pyrimidinium perchlorate and its complexes with prasedynium, neodymium, samarium and europium (00MI24) were characterized by UV spectroscopy. 

Figure 8.7. Delayed fluorescence and diffuse reflectance transient absorption spectroscopy on scattering substrates. Example terthicnyl on silica gel excited with = 354 nm (neodymium/yttrium-aluminum-garnet) (Nd/YAG) laser pulse of 10 nsec, 20 mj), recorded with a gated diode array spectrometer.

NBTC NC ND Nd YAG ndc NDR NEST NEXAFS Nanobiotechnology Center (Cornell University) nanocrystal nanodiamond neodymium-doped yttrium aluminium garnet (laser) 2,6-naphthalenedicarboxylate 2-nitro-jV-methyl-4-diazonium-formaldehyde resin New and Emerging Science and Technology near-edge x-ray absorption fine structure (spectroscopy)... 

Treatment of a suspension of Nd(NHPh)3(KCl)3 with trimethylalumi-num in hexane yielded the heteroleptic heterobimetallic cluster [Nd[(//.2-Me)2A/Me2]2(M3-NPh)(M2-Me)AlMe 2 in low yield (Fig. 29). The formation of the cyclic byproduct (Me2AlNHPh)3 was proven by means of NMR spectroscopy and X-ray crystallography [217]. The molecular structure of the Nd2Al6 dimer revealed the presence of a doubly deprotonated imido ligand bridging each a neodymium center and two aluminum atoms. 

Birnbaum, E.R. and Darnall, D.W. (1973) A study of carboxylic and amino acid complexes of neodymium(III) by difference absorption spectroscopy. Bioinorganic Chemistry, 3 (1), 15-26. 

Direct spectroscopic observation of the postulated diradical intermediates has not been possible so far. Thus, multiphoton infrared laser excitation of tetramethyldioxetane in the gas phase failed to detect diradical intermediates with lifetimes greater than about 5 nsec.Picosecond spectroscopy limited the lifetime of a diradical intermediate, if formed, to less than about lOpsec in the 264-nm pulsed photolysis of tetramethyldioxetane in acetonitrile, using a mode-locked neodymium... 

All these problems can be prevented as much as possible by using modern lasers as light source for Raman spectroscopy, for example, Neodymium-YAG laser. The intensity of the light can often be around 0.5 Watts. This laser device is installed in most modern Raman spectrometers. 

In this paper, oi and Al MASNMP. spectroscopy is used in conjunction with crystallinity, surface area and unit cell size measurements to study individual rare earth exchanged Y zeolites in order to determine the effect of individual rare earths cations on their structure and stability. These methods are used to further probe rare earth induced structural changes that occur during hydrothermal treatment of the zeolites. The studies were extended to also establish the effect of different lanthanum-cerium mixtures on zeolite stability. The data presented and discussed are for lanthanum, cerium, praseodymium and neodymium exchanged Y zeolites, as well as for zeolites exchanged with different lanthanum-cerium mixtures. 

Although first demonstrated by Chantry et al. in 1964, FT-Raman spectroscopy did not attract significant attention until the development of commercially available instrumentation with excitation in the near-infrared region (1064 nm) from a continuous wave Nd/YAG (neodymium-yttrium-aluminum-gamet) laser. The FT-Raman spectrometer is a frequency-division multiplexing system in which all (scattered) wave-... 

The steps and missteps in the process of discovering new elements led to caution in accepting a previously unidentified spectroscopic feature as evidence for a new element (Boyd 1959). Chemical characterization was required. For example, masurium was proposed for element 43, and illium and fiorentium were proposed for element 61 based on atomic spectroscopy of extracts from minerals. In retrospect, it is clear that there was evidence for unusual conditions for these elements. For example, above 7N the only mass numbers of stable isotopes of elements with odd atomic number are also odd, and there is only one stable isobar for each odd A. Molybdenum (Mo) has stable isotopes 92, 94—98, and 100. Ruthenium has 96, 98-102, and 104. Niobium has 93, and rhodium 103. Nothing is left for technetium, which would have the best chance for stability at mass numbers 97 and 99. Similarly, either neodymium or samarium has a 3-stable isotope fi om 142 to 150 nothing is left for promethium. 

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