Coldspray ionization

A different, but related ionization method is coldspray ionization (CSI) [14]. The ionization occurs in a similar manner to ESI, with the exception that the source housing and drying gas are cooled in order to stabilize weakly-bound ions. The effect is often incomplete desolvation and distributions of ions with different num-... 

There are only a few reports on the structures of active oxygen species formed on POMs. Recently, we have clarified some of the structures of the active oxygen species formed on POMs with nuclear magnetic resonance (NMR) spectroscopy, coldspray ionization mass spectrometry (CSI-MS), and single crystal X-ray structural analysis. In this section, we focus on the activation of H2O2 by the species (a)-(c) and present results from our recent studies. Some reaction mechanisms for H2O2-based oxidations by POMs are also described. 

After the treatment of 3a with H2O2 followed by the addition of an excess of diethyl ether, 3b could successfully be isolated. The positive-ion coldspray ionization mass spectrum of the isolated 3b showed a most intense parent ion peak centered at m/z = 3654.8 with an isotopic distribution that agreed with the calculated pattern of [(TBA)5SiWio032(02)2] - All these results show that the two 0x0 groups (O ) are replaced by two peroxo groups (C ) on the divacant lacunary site with retention of the y-Keggin framework (Eq. 4.2). 

Coldspray ionization (CSI) In MS, a variant of ESI operating at low source temperatures. 

Sakamoto, S. Fujita, M. Kim, K Yamaguchi, K. Characterization of self-assembling nano-sized structures by means of coldspray ionization mass spectrometry. Tetrahedron 2000, 56, 955. 

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