Spectroscopic characterization and photochemistry of the Criegee intermediate CF3C(H)OO

Bimolecular sinks of Criegee intermediates derived from hydrofluoroolefins – a computational analysis

“…This table shows a primitive calculation of the atmospheric impact of each reaction. If the k EFF value is written in italics, the dipole-dipole capture limit (k d-d ) was used to calculate the k EFF value because the master equation rate constant (k THEO ) exceeded the k d-d limit or because the reaction was barrierless 66,200 Therefore, the k UNI for CH 2 OO (∼0.3 s −1 ) is used here instead as it may be the closest analogue to that of syn-& anti-CF 3 CHOO. 42,70 On the basis of these premises, while the k UNI value used here is greater than many of the k EFF value for syn-& anti-CF 3 CHOO found in Table 6, the k EFF value for other reactions, particularly syn-& anti-CF 3 CHOO + (H 2 O) 2 , are greater still.…”

“…200 The unimolecular rate constant ( k UNI ) of a reaction path and k EFF are both equivalent and effective tools to show the efficiency of the respective reaction path as an sCI sink but, while Wang et al have identified syn - & anti -CF 3 CHOO experimentally, no k UNI values were identified in either the Wang et al or Guidry et al studies. 66,200 Therefore, the k UNI for CH 2 OO (∼0.3 s −1 ) is used here instead as it may be the closest analogue to that of syn - & anti -CF 3 CHOO. 42,70 On the basis of these premises, while the k UNI value used here is greater than many of the k EFF value for syn - & anti -CF 3 CHOO found in Table 6, the k EFF value for other reactions, particularly syn - & anti -CF 3 CHOO + (H 2 O) 2 , are greater still.…”

“…4,5,45,46,53,56 Only the bimolecular chemistry of CH 2 OO species has been explored in the experimental literature, although syn-& anti-CF 3 CHOO and syn-& anti-ClCHOO have been experimentally identied. [57][58][59][60][61][62][63][64][65][66] In a small number of studies, the bimolecular chemistry of HFO-sCIs has been interrogated using computational chemistry techniques: CH 2 OO somewhat exhaustively; [67][68][69][70][71] 72,73,77 The literature has very little analysis of syn-or anti-CF 3 CFOO. As much of the bimolecular chemistry of syn-& anti-FCHOO and syn-& anti-ClCHOO has already been previously studied in the computational literature, the HFO-sCIs explored herein are instead CH 2 OO, syn-CF 3 CHOO, anti-CF 3 CHOO, syn-CF 3 CFOO and anti-CF 3 CFOO, which are labelled as sCIs 1-5 and are displayed in Fig.…”

“…4,5,45,46,53,56 Only the bimolecular chemistry of CH 2 OO species has been explored in the experimental literature, although syn - & anti -CF 3 CHOO and syn - & anti -ClCHOO have been experimentally identified. 57–66 In a small number of studies, the bimolecular chemistry of HFO-sCIs has been interrogated using computational chemistry techniques: CH 2 OO somewhat exhaustively; 67–71 syn - & anti -FCHOO and syn - & anti -ClCHOO in reactions with CO 2 , H 2 , MeOH and CH 4 ; 72–76 and syn - & anti -CF 3 CHOO in reactions with CO 2 , CF 3 CHCH 2 and H 2 . 72,73,77 The literature has very little analysis of syn - or anti -CF 3 CFOO.…”