Acetone ionization potential

In the MS of oxetane the relative abundance of the ethylene radical ion is about eight times greater than that of the formaldehyde radical ion at the usual ionizing potential of 70 eV. However, 2,2-dimethyloxetane fragments much more to the radical ion of acetone... 

An electron impact study of 1,3-dichlorotetrafluoroacetone has provided a value of 11.95 e.v. for the appearance potential of the CF2C1+ ion. There is at present no value for the ionization potential of the CF2C1 radical available but it would be safe to assume that it would lie between the limits of 8.78 e.v. for CC13 and 10.0 e.v. for -CF3, so that the C-C bond strength will not differ greatly from that of acetone itself. 

Since the suggestion of the sequential QM/MM hybrid method, Canuto, Coutinho and co-authors have applied this method with success in the study of several systems and properties shift of the electronic absorption spectrum of benzene [42], pyrimidine [51] and (3-carotene [47] in several solvents shift of the ortho-betaine in water [52] shift of the electronic absorption and emission spectrum of formaldehyde in water [53] and acetone in water [54] hydrogen interaction energy of pyridine [46] and guanine-cytosine in water [55] differential solvation of phenol and phenoxy radical in different solvents [56,57] hydrated electron [58] dipole polarizability of F in water [59] tautomeric equilibrium of 2-mercaptopyridine in water [60] NMR chemical shifts in liquid water [61] electron affinity and ionization potential of liquid water [62] and liquid ammonia [35] dipole polarizability of atomic liquids [63] etc. 

Ionization potential of acetaldehyde, 123 acetone, 123 ammonia, 81 (z)-2-butcne, 48... 

APPI interface is promising since the common LC solvents are characterized by high first ionization potentials with the consequence that selective ionization of the analytes may occur. Addition of a dopant to the mobile phase such as acetone or toluene offers increased selectivity. 

Solvation of Pb(CH3)4 in solution increases along the series of solvents cyclohexane < 1,2-dimethoxyethane dioxane = hexamethylphosphoric acid triamide < pyridine < tetrahydrothiophene < triethylamine < tetrahydrofuran < triethylphosphane < N,N,N, N -tetramethylethylenediamine = acetone < dimethylformamide < dimethyl sulfoxide as derived from the increase of the NMR coupling constants J( H, Pb). Coordination of only one solvent molecule and trigonal bipyramidal geometry of the complexes was supposed [8]. For studies of the dispersion interaction of Pb(CH3)4 and various solvents, see [9, 28]. For a correlation of the ionization potential and the solvation energy of Pb(CH3)4 and other tetraorganometal compounds in acetonitrile, see [36]. 

For a series of oxyanions and a series of C=0 and N=0 compounds a linear correlation between (5( 0) and the inverse of the lowest energy n 7i transition was found. A linear correlation exists between acetone chemical shifts and the maximum of the n 71 transition for acetone-water solutions or for acetone in different solvents. Similar trends have also been observed in a variety of substituted acetophenones however, it was suggested that such trends may be fortuitous. In a series of aliphatic ethers a correlation between (5( 0) and the first ionization potential was suggested. 

Figure 9.18 illustrates the Audier-Stevenson rule in the case of ionized acetone. Will the rupture of the CH3OC-CH3 bond lead to the CH3CO+ ion and to the radical CH3 (pathway a) or to the CH3+ ion and to the radical CH3CO (pathway b) The ionization potential of the radical CHjCO- (680 kJ/mol) is inferior to that of the radical CH3 (946 kJ/mol) so the latter will be ionized. 

DNA sequencing and. 1113 Electrospray ionization (ESI) mass spectrometry, 417-418 Electrostatic potential map, 37 acetaldehyde, 688 acetamide, 791,922 acetate ion. 43. 53, 56, 757 acetic acid. 53. 55 acetic acid dimer, 755 acetic anhydride, 791 acetone, 55, 56. 78 acetone anion, 56 acetyl azide, 830 acetyl chloride, 791 acetylene. 262 acetylide anion, 271 acid anhydride, 791 acid chloride, 791 acyl cation, 558 adenine, 1104 alanine, 1017 alanine zwitterion, 1017 alcohol. 75 alkene, 74, 147 alkyl halide, 75 alkyne. 74... 

---