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Journal of Environmental Science and Health, Part A
Toxic/Hazardous Substances and Environmental Engineering

ISSN: 1093-4529 (Print) 1532-4117 (Online) Journal homepage: http://www.tandfonline.com/loi/lesa20

Prediction of the air-water partition coefficient for
perfluoro-2-methyl-3-pentanone using high-level
Gaussian-4 composite theoretical methods
Sierra Rayne & Kaya Forest
To cite this article: Sierra Rayne & Kaya Forest (2014) Prediction of the air-water partition
coefficient for perfluoro-2-methyl-3-pentanone using high-level Gaussian-4 composite
theoretical methods, Journal of Environmental Science and Health, Part A, 49:11, 1228-1235,
DOI: 10.1080/10934529.2014.910033
To link to this article: http://dx.doi.org/10.1080/10934529.2014.910033

Published online: 26 Jun 2014.

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Date: 23 September 2015, At: 14:10

Journal of Environmental Science and Health, Part A (2014) 49, 1228–1235
Copyright © Taylor & Francis Group, LLC
ISSN: 1093-4529 (Print); 1532-4117 (Online)
DOI: 10.1080/10934529.2014.910033

Prediction of the air-water partition coefficient for perfluoro-2methyl-3-pentanone using high-level Gaussian-4 composite
theoretical methods
SIERRA RAYNE1 and KAYA FOREST2
1

Chemologica Research, Mortlach, Saskatchewan, Canada
Department of Environmental Engineering, Saskatchewan Institute of Applied Science and Technology, Moose Jaw,
Saskatchewan, Canada

Downloaded by [The University of British Columbia] at 14:10 23 September 2015

2

The air-water partition coefficient (Kaw) of perfluoro-2-methyl-3-pentanone (PFMP) was estimated using the G4MP26 G4
levels of theory and the SMD solvation model. A suite of 31 fluorinated compounds was employed to calibrate the
theoretical method. Excellent agreement between experimental and directly calculated Kaw values was obtained for the
calibration compounds. The PCM solvation model was found to yield unsatisfactory Kaw estimates for fluorinated
compounds at both levels of theory. The HENRYWIN Kaw estimation program also exhibited poor Kaw prediction
performance on the training set. Based on the resulting regression equation for the calibration compounds, the G4MP2-SMD
method constrained the estimated Kaw of PFMP to the range 5–8 £ 10¡6 M atm¡1. The magnitude of this Kaw range
indicates almost all PFMP released into the atmosphere or near the land-atmosphere interface will reside in the gas phase,
with only minor quantities dissolved in the aqueous phase as the parent compound and6 or its hydrate6 hydrate conjugate
base. Following discharge into aqueous systems not at equilibrium with the atmosphere, significant quantities of PFMP will
be present as the dissolved parent compound and6 or its hydrate6 hydrate conjugate base.
Keywords: Perfluoro-2-methyl-3-pentanone, perfluorinated compounds, air-water partitioning, theoretical study, quantum chemistry
composite methods.

Introduction
Perfluoro-2-methyl-3-pentanone (PFMP; heptafluoroisopropyl pentafluoroethyl ketone; 2-trifluoromethyl-1,1,1,2,
4,4,5,5,5-nonafluoro-3-pentanone) is a recently developed
fluorinated ketone Halon replacement intended as a fire
suppressant and known by the names Novec 6496 1230
and FK-5-1-12.[1–3] In the atmosphere, this compound
exhibits negligible ozone depletion (ODP D 0) or global
warming potential (direct and indirect GWP each <1)
nor reaction with hydroxyl radicals (kOH < 5 £ 10¡16
cm3 molecule¡1 s¡1) and has an estimated lifetime
of between 4 and 15 days due to photolysis.[4–6] At temperatures < 500 C, no measurable thermal degradation
takes place.[3]
To better understand its fate in natural and engineered
systems, including in vivo, higher quality estimates of
Address correspondence to Sierra Rayne, Chemologica
Research, Mortlach, Saskatchewan S0H 3E0, Canada; E-mail:
sierra.rayne@live.co.uk
Received January 31, 2014.

PFMP’s partitioning behavior are required. The only published air-water partition coefficient (Kaw) in the open literature for PFMP appears to be a value of 8 £ 10¡6 M
atm¡1 estimated based on its solubility in water
(0.0032 mol m¡3) and vapor pressure (0.4 atm).[3] As has
been previously shown,[7–9] significant difficulties generally
arise when trying to either experimentally measure or estimate using low-level computational approaches the physico-chemical properties of perfluorinated compounds.
Thus, in the current study we employ high-level Gaussian-4
composite theoretical methods and multiple solvation
models with the goal of accurately estimating the Kaw of
PFMP for comparison with the prior experimental estimate
and values obtained by less rigorous in silico predictions.

Materials and methods
Gas and aqueous phase calculations were performed
at the G4MP2[10] and G4[11] levels of theory using
the Gaussian 09 (G09)[12] software program. Aqueous
phase studies were conducted with the SMD[13] and

1229

Gaussian-4 composite methods to predict partition coefficients
PCM [14–17] solvation models. Molecular structures
were visualized using Avogadro v1.0.3 [18] and Gabedit
v2.4.3.[19] All gas and aqueous phase optimized structures
were confirmed as true minima by vibrational analysis at
the same level.

Kaw values of these molecules were calculated at the
G4MP2 and G4 levels of theory using the SMD solvation
model. Additional Kaw estimates were obtained with the
bond and group methods in the HENRYWIN module of
EPI Suite (v. 4.11; November 2012)[21] via the SMILES
molecular language.[22,23]
Kaw estimates for chloropentafluoroethane, 1,2-dichloro-1,
1,2,2-tetrafluoroethane, 1,1,2-trichloro-1,2,2-trifluoroethane,
difluoromethane, fluoroethane, 1,1,1,2-tetrafluoroethane,
1- and 2-fluoropropane, 1,1-difluoroethene, tetrafluoroethene,
hexafluoropropene, and trifluoromethylbenzene were
not available using the group method within HENRYWIN,

Results and discussion

Downloaded by [The University of British Columbia] at 14:10 23 September 2015

For benchmarking the theoretical methods, a suite of 31
fluorinated organic compounds having well-constrained
Kaw values [20,21] were chosen (Table 1). The corresponding

Table 1. Experimental and calculated air-water partition coefficients for the 31 fluorinated organic calibration compounds at the
G4MP2 and G4 levels of theory with the SMD and PCM solvation models, as well as the HENRYWIN bond and group methods.
SMD
ID
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31

Compound
Chlorodifluoromethane
Chloropentafluoroethane
Chlorotrifluoromethane
Dichlorodifluoromethane
1,2-Dichloro-1,1,2,
2-tetrafluoroethane
Trichlorofluoromethane
1,1,2-Trichloro-1,2,
2-trifluoroethane
Fluoromethane
Difluoromethane
Trifluoromethane
Tetrafluoromethane
Fluoroethane
1,1-Difluoroethane
1,1,1,2-Tetrafluoroethane
Hexafluoroethane
1-Fluoropropane
2-Fluoropropane
Octafluorocyclobutane
1,1-Difluoroethene
Tetrafluoroethene
Hexafluoropropene
2,2,2-Trifluoroethanol
1,1,1-Trifluoro-2-propanol
2,2,3,3-Tetrafluoro1-propanol
2,2,3,3,3-Pentafluoro1-propanol
1,1,1,3,3,3-Hexafluoro2-propanol
Fluorobenzene
1,2-Difluorobenzene
1,3-Difluorobenzene
1,4-Difluorobenzene
Trifluoromethylbenzene

Expt.

G4MP2

PCM
G4

HENRYWIN

G4MP2

G4

¡1

0.3-2.5 £ 10
3.2-3.8 £ 10¡4
5.8-9.4 £ 10¡4
0.3-3.1 £ 10¡3
8.2-8.3 £ 10¡4

¡2

9.9 £ 10
8.6 £ 10¡5
4.7 £ 10¡4
1.1 £ 10¡3
1.7 £ 10¡4

¡2

9.8 £ 10
8.4 £ 10¡5
4.6 £ 10¡4
1.0 £ 10¡3
1.7 £ 10¡4

1.1 £ 10
1.5 £ 10¡1
1.1 £ 10¡1
1.2 £ 10¡1
1.6 £ 10¡1

0.1-1.7 £ 10¡2
2.0-3.4 £ 10¡3

3.0 £ 10¡3
3.8 £ 10¡4

2.9 £ 10¡3
3.7 £ 10¡4

5.2-7.2 £ 10¡2
8.7 £ 10¡2
1.1-1.4 £ 10¡2
1.9-2.1 £ 10¡4
4.4 £ 10¡2
3.7-5.4 £ 10¡2
1.8 £ 10¡2
4.9-5.9 £ 10¡5
6.2 £ 10¡2
5.9 £ 10¡2
1.2-2.5 £ 10¡4
2.5 £ 10¡3
1.6 £ 10¡3
2.9 £ 10¡4
5.8-5.9 £ 101
4.5-4.6 £ 101
1.6 £ 102

8.9 £ 10¡2
3.9 £ 10¡1
7.9 £ 10¡2
2.8 £ 10¡4
2.2 £ 10¡1
6.1 £ 10¡1
2.6 £ 10¡1
6.6 £ 10¡5
2.1 £ 10¡1
3.0 £ 10¡1
5.4 £ 10¡4
2.1 £ 10¡3
1.1 £ 10¡4
5.7 £ 10¡4
9.7 £ 101
3.9 £ 101
5.2 £ 102

4.5 £ 101

bond

Group

1.1 £ 10
1.4 £ 10¡1
1.1 £ 10¡1
1.2 £ 10¡1
1.6 £ 10¡1

¡3

9.7 £ 10
1.2 £ 10¡4
6.2 £ 10¡4
3.5 £ 10¡3
6.6 £ 10¡4

4.7 £ 10¡2
n6 a
7.2 £ 10¡4
2.8 £ 10¡3
n6 a

1.5 £ 10¡1
1.9 £ 10¡1

1.4 £ 10¡1
1.8 £ 10¡1

2.0 £ 10¡2
3.7 £ 10¡3

1.0 £ 10¡2
n6 a

8.8 £ 10¡2
3.8 £ 10¡1
7.6 £ 10¡2
2.7 £ 10¡4
2.2 £ 10¡1
5.9 £ 10¡1
2.5 £ 10¡1
6.4 £ 10¡5
2.0 £ 10¡1
3.0 £ 10¡1
4.7 £ 10¡4
2.1 £ 10¡3
1.1 £ 10¡4
5.8 £ 10¡4
1.0 £ 102
4.1 £ 101
5.6 £ 102

1.4 £ 100
3.9 £ 100
1.8 £ 100
1.0 £ 10¡1
1.7 £ 100
4.6 £ 100
5.1 £ 100
1.4 £ 10¡1
1.5 £ 100
2.0 £ 100
5.8 £ 10¡1
2.9 £ 10¡1
1.9 £ 10¡1
6.0 £ 10¡1
4.7 £ 101
2.4 £ 101
1.2 £ 102

1.4 £ 100
3.8 £ 100
1.7 £ 100
1.0 £ 10¡1
1.6 £ 100
4.4 £ 100
5.0 £ 100
1.4 £ 10¡1
1.5 £ 100
2.0 £ 100
5.0 £ 10¡1
2.9 £ 10¡1
1.8 £ 10¡1
5.9 £ 10¡1
4.7 £ 101
2.4 £ 101
1.2 £ 102

6.1 £ 10¡2
3.4 £ 10¡3
1.7 £ 10¡3
2.2 £ 10¡4
4.6 £ 10¡2
2.6 £ 10¡3
6.5 £ 10¡4
4.1 £ 10¡5
3.4 £ 10¡2
3.4 £ 10¡2
1.3 £ 10¡5
4.4 £ 10¡3
1.2 £ 10¡3
1.9 £ 10¡4
3.5 £ 101
2.7 £ 101
1.6 £ 101

5.9 £ 10¡2
n6 a
1.1 £ 10¡2
8.5 £ 100
n6 a
4.9 £ 10¡2
n6 a
4.1 £ 10¡4
n6 a
n6 a
4.1 £ 10¡6
n6 a
n6 a
n6 a
8.5 £ 101
3.6 £ 101
4.3 £ 102

1.9 £ 101

2.0 £ 101

5.6 £ 101

5.6 £ 101

6.8 £ 100

8.5 £ 100

2.4 £ 101

7.9 £ 101

8.9 £ 101

2.0 £ 102

2.1 £ 102

3.4 £ 100

1.5 £ 101

1.2-1.6 £ 10¡1
1.4 £ 10¡1
1.3 £ 10¡2
1.3 £ 10¡1
6.2-6.3 £ 10¡2
MSE [log10 Kaw]
MAE [log10 Kaw]
RMSE [log10 Kaw]

1.2 £ 10¡1
8.3 £ 10¡2
9.7 £ 10¡2
1.2 £ 10¡1
5.1 £ 10¡2
0.12
0.46
0.57

1.2 £ 10¡1
8.5 £ 10¡2
8.7 £ 10¡2
1.2 £ 10¡1
5.1 £ 10¡2
0.11
0.46
0.57

1.1 £ 100
2.0 £ 100
1.5 £ 100
2.0 £ 100
2.3 £ 100
1.66
1.69
1.92

1.1 £ 100
2.0 £ 100
1.5 £ 100
2.0 £ 100
2.3 £ 100
1.65
1.68
1.91

1.6 £ 10¡1
1.4 £ 10¡1
1.4 £ 10¡1
1.4 £ 10¡1
2.1 £ 10¡2
-0.33
0.47
0.66

6.6 £ 10¡2
2.4 £ 10¡2
2.4 £ 10¡2
2.4 £ 10¡2
n6 a
0.08
0.62
1.20

0

0

Notes. Values are in M atm¡1. MSE D mean signed error, MAE D mean absolute error, and RMSE D root mean squared error.

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1230
nor will this method calculate the Kaw for the target analyte
(PFMP). Although its mean signed error (MSE), mean absolute error (MAE), and root mean squared error (RMSE)
of 0.08, 0.62, and 1.20 log 10 units, respectively, for the
19 remaining compounds were promising, the method
yielded a gross error for tetrafluoromethane (experimental
Kaw D 1.9–2.1 £ 10¡4 M atm¡1; predicted Kaw D 8.5 £ 100
M atm¡1) suggesting inherent difficulties with some perfluorinated molecules. Consequently, the HENRYWIN
group method was omitted from further consideration. The
HENRYWIN bond method gave Kaw MSE, MAE, and
RMSE of ¡0.33, 0.47, and 0.66 log10 units, respectively,
with an estimated Kaw for PFMP of 2.2 £ 10¡3 M atm¡1
that positively deviates from the prior K aw report of
8 £ 10¡6 M atm¡1 [3] by 2.44 log10 units.
For a number of the training set compounds, multiple
potential conformers are present (Figures 1 and 2), which
necessitated consideration for the G4MP2 and G4 calculations. In both the gas and aqueous phase (including both
the SMD and PCM solvation models), geometry optimizations and frequency calculations for each of these possible
conformers were conducted using the G4MP2 and G4
methods. Relative standard state (298.15 K and 1 atm
[gas]6 1 M [aqueous]) free energies (DDG ) are shown in
Figures 1 and 2 next to each conformer. The resulting Kaw
value for each compound was calculated using the lowest
energy conformer in each phase.
Excellent agreement was obtained between experimental
and the G4MP2 (MSE6 MAE6 RMSE D 0.126 0.466 0.57
log10 units) and G4 (MSE6 MAE6 RMSE D 0.116
0.466 0.57 log10 units) Kaw values using the SMD solvation
model, with comparatively poor agreement via the PCM
solvation model at these two levels of theory (G4MP2:

Rayne and Forest
MSE6 MAE6 RMSE D 1.666 1.696 1.92; G4: MSE6
MAE6 RMSE D 1.656 1.686 1.91 log10 units) (Table 1 and
Figure 3). Results obtained with the PCM model are too
unreliable for rigorous Kaw estimates on fluorinated
compounds.
Calculations at the G4MP2 level with the SMD solvation model yield a direct Kaw of 3.8 £ 10¡6 M atm¡1 for
PFMP. Two conformers were identified, with one substantially more energetically stable (by »8 kJ6 mol in the gas
phase and »12 kJ6 mol in the aqueous phase) than the
other (Figure 4). When corrected using the calibration
equation shown in Figure 3(a), the adjusted Kaw for this
compound is 4.9 £ 10¡6 M atm¡1. Both of these values
are in excellent agreement with the previously published
value of 8 £ 10¡6 M atm¡1.[3] Calculations on PFMP
using the G4 method were too computationally expensive.
However, based on the effective equivalence in Kaw predictions using the G4MP2 and G4 methods with the SMD
solvation model on smaller fluorinated compounds, it is
anticipated that G4-SMD calculations on PFMP would
provide a Kaw value essentially equal to that obtained at
the less expensive G4MP2 level.
As a result, our work helps constrain the Kaw value of
PFMP to the range from 4–8 £ 10¡6 M atm¡1, and more
likely to the narrower range of 5–8 £ 10¡6 M atm¡1. In aqueous systems open to the atmosphere, PFMP can undergo [24]
the following equilibrium processes (Eqs. (1)–(3); Figure 5):
PFMP . g / fi PFMP . aq /

(1)

PFMP . aq / fi PFMP-diol . aq /

(2)

PFMP-diol . aq / fi PFMP-diol-anion . aq /

(3)

Fig. 1. Relative gas (298.15 K, 1 atm) and aqueous (298.15 K, 1 M) phase standard state free energies for the conformers of 1,2dichloro-1,1,2,2-tetrafluoroethane (5), 1,1,2-trichloro-1,2,2-trifluoroethane (7), 1-fluoropropane (16), 2,2,2-trifluoroethanol (22),
1,1,1-trifluoro-2-propanol (23), and 2,2,3,3,3-pentafluoro-1-propanol (25) at the G4MP2 and G4 levels of theory with the SMD and
PCM solvation models.

Downloaded by [The University of British Columbia] at 14:10 23 September 2015

Gaussian-4 composite methods to predict partition coefficients

1231

Fig. 2. Relative gas (298.15 K, 1 atm) and aqueous (298.15 K, 1 M) phase standard state free energies for the conformers of 2,2,3,3tetrafluoro-1-propanol (24) at the G4MP2 and G4 levels of theory with the SMD and PCM solvation models.

The dimensionless Kaw for PFMP (K1) is estimated at 1.2–
2.0 £ 10¡4 based on the findings herein and K2 has been
previously estimated at between 0.14 and 0.37.[25] K3 is pH
dependent with PFMP-diol(aq) having an estimated pKa of
7.11.[25,26]
The dominant fate of PFMP will depend on the matrix
into which it is initially deposited and whether that matrix
is at equilibrium with other relevant matrices. Using average values of K1 D 1.6 £ 10¡4 and K2 D 0.26, the pH
dependent percentage fractions (ai) of total PFMP present
as PFMP(g), PFMP(aq), PFMP-diol(aq), and PFMP-diolanion(aq) in an aqueous system at equilibrium with the
atmosphere are shown in Figure 6(a) between pH 4 and
10. From pH 4.0 up to 8.2, > 99.9% of PFMP will be present in the gas phase when atmospheric equilibration is
allowed, decreasing only modestly to »97% at pH 10.
Thus, for aquatic systems at equilibrium with the atmosphere, the dominant proportion of PFMP discharged into
aquatic systems will move into the gas phase and be subject to relatively rapid photolysis. Where PFMP is discharged into the atmosphere and6 or onto the land, the
atmospheric reservoir will also be dominant.
However, not all natural (e.g., groundwaters and in
vivo) and engineered (e.g., water6 wastewater treatment
processes) aquatic systems are equilibrated with the atmosphere. [27,28] For aquatic systems not equilibrated with the
atmosphere following PFMP discharge into the aqueous
phase, significant quantities of PFMP may be present in

solution, particularly as the hydrate and6 or dissociated
diol-anion depending on pH (Figure 6(b)), ranging from
»21% between pH 4.0 and 5.5 and rising rapidly at pH >
5.5 up to effectively 100% at pH 10.
Subsequent rapid hydrolysis of dissolved phase PFMP is
anticipated. It appears the only open source report on the
hydrolytic lifetime (thyd) of PFMP is Ref.,[6] which reports
a thyd of 1.5 § 0.1 h at pH 5.6 and 0.9 § 0.1 h at pH 8.5.
At this point, the accuracy of these thyd values are poorly
defined. The authors appear to have monitored the hydrolytic degradation of PFMP via 19F NMR. The starting
concentration of PFMP, which is a dense, colorless liquid
under ambient conditions, in the NMR tube was 2.4% by
volume in an aqueous solution. Using a PFMP density of
1600 kg m¡3 at 298 K,[2] a molecular mass of 316.04 g
mol¡1, and a reported PFMP water solubility of
0.0032 mol m¡3,[3] the 19F NMR hydrolysis experiments
appear to have been conducted at a PFMP concentration
about 4.6 orders of magnitude above the solubility limit
for this compound.
These authors[6] expressed surprise at not seeing the
PFMP-diol during their experiments (whose absence contradicted their own calculations), but based on the preceding calculations, this is to be expected. It appears that
since PFMP was present in the NMR tube at several
orders of magnitude above its solubility limit, and thereby
almost entirely present as a pure liquid phase, that a negligible fraction of PFMP was actually dissolved.

Rayne and Forest

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1232

Fig. 3. Experimental versus calculated air-water partition coefficients (Kaw) for the 31 fluorinated organic calibration compounds at
the G4MP2 and G4 levels of theory with the SMD and PCM solvation models, as well as the HENRYWIN bond and group methods. Best-fit regression lines (solid), 1:1 lines (dashed), and the regression statistics are provided with each plot.

Gaussian-4 composite methods to predict partition coefficients

Downloaded by [The University of British Columbia] at 14:10 23 September 2015

Fig. 4. Relative gas (298.15 K, 1 atm) and aqueous (298.15 K,
1 M) phase standard state free energies for the conformers of
perfluoro-2-methyl-3-pentanone (PFMP) at the G4MP2 level of
theory with the SMD solvation model.

Consequently, any NMR signals from PFMP-diol present
during the hydrolysis experiments would be overwhelmed
by corresponding signals from the liquid phase starting
material present in massive excess.

1233

It is unclear how a reliable hydrolysis rate constant,
which by definition necessitates measuring the rate at
which dissolved starting material is hydrolyzed to dissolved product, can be measured on an experimental system in which the starting material appears to have greatly
exceeded solubility limitations, thereby being present dominantly as a pure (undissolved) phase. In addition, the proposed hydroxide ion hydrolysis mechanism for PFMP
(Figure 7) that is expected to be dominant in aqueous solution at near-neutral and alkaline pH values involves the
PFMP-diol-anion generated after the rate-determining
step (RDS) by hydroxide ion attack on PFMP. Thus, at
pH values where PFMP can be hydrated to PFMP-diol
and the resulting hydrate dissociates to the PFMP-diolanion which itself can undergo an apparently rapid intramolecular degradation, the hydration mechanism could be
competitive with direct hydroxide ion attack and yield the
same final products. Further experimental work appears

Fig. 5. Equilibrium partitioning and reaction series showing the dissolution of PFMP (PFMP(g)!PFMP(aq)), its hydration
(PFMP(aq)!PFMP-diol(aq)), and the dissociation of the PFMP hydrate (PFMP-diol(aq)!PFMP-diol-anion(aq)).

Fig. 6. pH-dependent distribution diagrams showing the fraction of total PFMP present in the gas phase (PFMP(g)) and dissolved in
aqueous solution as the parent compound (PFMP(aq)), hydrate (PFMP-diol(aq)), and hydrate conjugate base (PFMP-diol-anion(aq))
as a function of pH between pH 4 and 10 in (a) a system at equilibrium with the atmosphere and (b) a system without atmospheric
equilibration.

Fig. 7. Proposed mechanism for the hydrolysis of PFMP by hydroxide ion.

1234
warranted to better elucidate the relative importance of
these two mechanisms.

Downloaded by [The University of British Columbia] at 14:10 23 September 2015

Conclusions
High-level G4MP2 and G4 composite method calculations
have constrained the estimated air-water partition coefficient (Kaw) of perfluoro-2-methyl-3-pentanone (PFMP) to
between 5–8 £ 10¡6 M atm¡1. In aquatic systems at equilibrium with the atmosphere, almost all PFMP will be
present in the gas phase, with only minor quantities dissolved in the aqueous phase as the parent compound
and6 or its hydrate6 hydrate conjugate base. However, in
aquatic systems not equilibrated with the atmosphere and
subject to direct PFMP inputs, significant quantities of
PFMP will be present as the dissolved parent compound
and6 or its hydrate6 hydrate conjugate base, necessitating
their inclusion in ecological and human health modeling
efforts.

Funding
This work was supported by a SIAST Seed Applied
Research Program grant to K. Forest, and was made possible by the facilities of the Western Canada Research
Grid (WestGrid: Project 100185), the Shared Hierarchical
Academic Research Computing Network (SHARCNET:
Project sn4612), and Compute6 Calcul Canada.

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[2] Gustavsson, J.P.R.; Segal, C. Characterization of a perfluorinated
ketone for LIF applications (AIAA 2008-259). In 46th AIAA Aerospace Sciences Meeting and Exhibit, Reno, NV, January 7–10;
American Institute of Aeronautics and Astronautics: Reston, VA,
2008.
[3] Owens, J.G. Understanding the Stability and Environmental Characteristics of a Sustainable Halon Alternative; 3M Performance
Materials, 3M Center: St. Paul, MN, 2003.
[4] Taniguchi, N.; Wallington, T.J.; Hurley, M.D.; Guschin, A.G.;
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[5] D’Anna, B.; Sellevag, S.R.; Wirtz, K.; Nielsen, C.J. Photolysis
study of perfluoro-2-methyl-3-pentanone under natural sunlight
conditions. Environ. Sci. Technol. 2005, 39, 8708–8711.
[6] Jackson, D.A.; Young, C.J.; Hurley, M.D.; Wallington, T.J.;
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Gaussian-4 composite methods to predict partition coefficients

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