Detection of quasimolecular ion of Cu(hfac)(tmvs) by ion attachment mass spectrometry

Abstract

A molecular ion of (trimethylvinylsilane)(1,1,1,5,5,5-hexafluoroacetyl-acetonato)Cu(I) [Cu(hfac)(tmvs)], which could not be detected by mass spectrometry with conventional ionization techniques such as electron impact ionization because of weak coordination bonds, has been successfully detected as a quasimolecular ion, Cu(hfac)(tmvs)Li+, for the first time by recently developed ion-attachment mass spectrometry (IAMS). Cu(hfac)(tmvs) is a material widely used in the metal organic chemical vapor deposition (MOCVD) process. In the thermal decomposition of Cu(hfac)(tmvs), trimethylvinylsilane (tmvs) and hexafluoroacetylacetone (Hhfac) were observed by IAMS as the reaction products. We also evaluated the dependence of the decomposition process on temperature. We found IAMS to be an effective tool in monitoring and clarifying MOCVD processes.

Determination of Acetone in Human Breath by Lithium Ion Attachment Mass Spectrometry

“…13), 17), 19) Therefore, the H 2 O gas works as a third body to remove any excess energy from the acetone adduct ion during the ion attachment process. 15), 16) In practice, when the standard acetone sample of 100 ppbv was measured with various water vapor concentrations (1῍100 ppmv; parts per million by volume), the same peak intensity was obtained for the standard sample. Thus, the matrix e#ect of H 2 O on the determination of acetone was shown to be negligible when using this method.…”

“…15) Thus, the analyte target molecules e#ectively become [M῍Li] ῍ that are stabilized by third-body gases, such as in matrices like N 2 and H 2 O, which remove any excess energy of the adduction. 16) Li ion a$nity also a#ects the relative sensitivity of the analysis, depending on the polarity and structure of compounds. 15), 17) The relative sensitivity for acetone is higher by 10 5 times than that of N 2 at 100 Pa. 17) Therefore, the sensitivity of the IAMS system is high enough to analyze acetone at ppbv levels or lower in exhaled breath without any preconcentration.…”

Development of lithium attachment mass spectrometry – knudsen effusion and chemical ionisation mass spectrometry (KEMS, CIMS)

“…Fujii and Ohta 5 investigated several lithium bearing materials (Li 2 O, Li 2 SiO 3 , Li 3 PO 4 , zeolite A and β-eucryptite) as potential sources for lithium ion production. β-eucryptite was shown to provide the highest emission current densities (2 × 10 −6 A cm −2 ) and is the material used by Fujii et al, 4 Selvin and Fujii, 6 Nakamura et al, 7 and Edwards et al 8 Presented here are initial results from the testing and construction of lithium-ion attachment sources for two different mass spectrometers. First, a Chemical Ionization Mass Spectrometer (CIMS) used for making trace gas phase measurements will be modified.…”

“…Fujii et al, 4 Selvin and Fujii, 6 Nakamura et al, 7 and Edwards et al, 8 have made β-eucryptite from heating a crushed mix of Al 2 O 3 : SiO 2 : Li 2 O in a 1 : 1 : 1 molar ratio. In this work filaments were using Al 2 O 3 : SiO 2 : Li 2 O and Al 2 O 3 : SiO 2 : Li 2 CO 3 , both with 1 : 1 : 1 molar ratios.…”

Application of Ion Attachment Mass Spectrometry to Evolved Gas Analysis for in Situ Monitoring of Porous Ceramic Processing

“…Very recently, IAMS has been developed by Fujii et al, − who named the technique “ion attachment mass spectrometry for Li + CI mass spectrometry”, IA ionization offers completely soft ionization of gaseous species, including radical species. These features of IAMS have permitted Nakamura et al to successfully detect and monitor the products of the thermal decomposition of a key material in the metal oxide chemical vapor deposition process. Fujii et al developed an apparatus for the analysis of ambient air at atmospheric pressure that could be coupled to a system for supercritical fluid chromatography.…”