This extremely succinct slide illustrates my research interests and plans, as well as my academic/industry timeline. Let me know what you think and feel free to email with with specific questions.

1. www.nasa.gov
HOMO dimer LUMO dimerEs-t of 20 kcal/mol
Estimated binding
energy of 33
kcal/mol
Towards a Deeper Understanding of Thermochemical Energy
Conversion through Flames
Enoch Dames
edames@mit.edu
Department Chemical Engineering
Massachusetts Institute of Technology
Cambridge, MA, 02139-4307, USA
Soot formation: an unresolved problem
Quantum chemistry and rate theory for advanced fuels
Los Angeles Hong Kong The number of transport vehicles (e.g., cars and planes) is
expected to increase by 35% over the next 25 years.1 And
unfortunately, soot’s contribution to global climate forcing
effects was recently shown to be significantly greater than
previously thought and only second to CO2
2:
CO2 – 1.7 W/m2
Soot - 1.1 W/m2
Although millions of premature deaths per year are
attributed to soot production, the scientific community still
doesn’t have a clear picture of how soot is formed. Thus
arises the age-old question – how can you change something
you don’t understand?
1http://www.eia.gov/
2Bond et al. 2013, J. Geophys. Res.
A dual purpose vision: uncovering aspects of soot formation, which can lead to
A – new insights for mitigation, B – novel uses and materials
burner
flame
fuel + oxidizer
CO, H2, CO2, H2O, C2H2
burner
flame
fuel + oxidizer
CO, H2, CO2, H2O, C2H2
combustion
soot formation
Current applications for flame synthesis of
nanoparticles:
• carbon black for tires
• TiO2 and other metal oxide nanopowders for
paint, solar and fuel cells
• thin diamond films for semiconductors
• optoelectronics applications & luminescent
materials
• more recently: carbon nanotubes and
buckminsterfullerenes , quantum dots,
composites, catalysts
0
10
20
30
40
50
60
0 2 4 6 8
M06-2X/6-31+G(d,p) Isodesmic
Scwarc 1951
ONIOM
CentralBDE(kcal/mol)
1 Szwarc, M. Proc. Roy. Soc. (London) A Math. Phys. Sci. 1951, 207, 5.
2 Vreven, T.; Morokuma, K. J. Phys. Chem. A 2002, 106, 6167.
Synthesizing chemicals, fuels, and particles
The evidence:
• H2 and CO are major combustion products (see
second picture to the right)
• FTIR, SEM, AFM evidence for aliphatic functional
groups on nacent soot (Wang, 2012 Proc. Combust.
Inst.)
• [Persistent] free radicals shown to exist in soot
(radicals are necessary for molecular growth
processes and can act as catalytic sites for
polymerization of hydrocarbon chains)
Goal: uncover thermodynamic driving force(s) for bulk
phase carbon growth and surface growth through a
combined multi-scale computational-experimental
approach
2 2
1
1
2
n m
m
CO H C H H O
n n
 
    
 
unique structure-specific electronic properties
may lead to better understanding of PAH
stacking at high temperature
Propulsion and the role of combustible energy sources
Tesla Model S battery:  1 MJ/kg Ford Model T gasoline engine:  45 MJ/kg
*pictures form Tesla and the Antique Automobile Club of America
Like it or not, fossil fuels continue to be relied upon.
1) they’re accessible and cheap
2) they have high energy density
3) less developed nations can’t afford to embark on
advanced alternative fuel projects
My research plans in the area of propulsion concern the
multi-scale modeling and chemistry necessary for
advancing air and ground transportation technologies.
This work involves identifying key rate limiting steps for a
wide range of engine types and conditions, with focus on
aeropropulsion and high speed/hypersonic [turbulent]
combustion, as well as high-performance and efficient
combustion (e.g. HCCI and RCCI engines)
Target compounds and fuels are those that can be
generated from petroleum/fossil fuel alternatives. (e.g.,
biofuels, solar fuels, Fischer-Tropsch fuels)
Boeing
R. Reitz, U Wisconsin
The picture to the right serves as a model
for a particular bond type possible in soot,
across two PAH/graphene sheets. Very weak
carbon-carbon bond dissociation energies
(BDEs), illustrated below, can lead to
persistent free-radicals in soot.
This poster details my academic research proposal and interests, previous work, and path
leading to the present day. I am a physical chemist and a mechanical engineer. Soot
formation and nanoparticle synthesis, catalytic upconversion of syngas, propulsion, the
chemistry of alternative fuels and natural gas, are all among my evolving academic foci.
For a list of my publications, my teaching and service experience, please refer to my CV
(which can be found at http://cheme.scripts.mit.edu/green-group/enoch-dames)
B.S., Engineering Science
and Mechanics
B.A., Chemistry
High Temperature
Gas Dynamics Lab
Biophysics (2002) Tissue Engineering (2004)
Maui Space
Surveillance Site
GE Global Research,
Thermal System Lab
DOE/Princeton Fellowship
20122005 20062002 2004
Ph.D., Mechanical
Engineering
Hypothesis: Fischer Tropsch like kinetics are
occurring on the surface of soot:
Burner-stabilized
premixed flame
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0
500
1000
1500
2000
0 0.5 1 1.5 2 2.5 3 3.5 4
T(K)
Distance From Burner (cm)
MoleFraction
O2
CO
fuel
H2O
T
H2
CO2
90
Although soot has been studied for decades, it has only recently been observed that hydrocarbon
chains can form on its surface under some flame conditions – can we exploit this process to
upconvert syngas or natural gas to valuable chemical feedstocks, or even transportation fuels?
RelativeRadicalConc.
Time
Hours
Days
Months
Indefinite
adopted from Gehling and Dellinger, 2013, Environ. Sci. Tech.
Vander Wal and
Tomasek, 2003,
Combust. Flame
2003
A dirty snow
cone melts
faster
Flames offer scalable
means of producing
nanoparticles
Looking back at the experiment (Abid et al. 2008),
where does this surface growth process occur?
liquid-like shells of
soot particles
Much of my previous and current work has involved developing detailed kinetic models for H2/CO,
natural gas, alkanes, aromatics, and oxygenated fuels. Quantum chemistry and advanced rate
theory are utilized to predict phenomenological rates as a function of temperature and pressure.
An array of methods are used to develop and validate detailed kinetic models. Generalized rate
rules for oxygenated fuel combustion are also currently being developed.




105
106
107
108
109
1010
1011
1012
0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.20
1000 K / T
rate,s-1
6pp
6pp
6pt
6ps
Dashed lines: H-shifts, nomenclature:
6ps = 6-membered ring TS between a
primary and secondary radical site
Solid lines: -scission to CH2O and an
alkyl radical
: crossover temperature
See
http://rmg.mit.edu/
for more information
on automated
mechanism
development
0
50
100
150
200
250
300
0 500 1000 1500 2000 2500 3000
[OH],ppm
Time, microseconds
OH
1542 K
1.42 atm
1486 K
1.52 atm 1377 K
1.54 atm
1343 K
1.61 atm
0
20
40
60
80
0 50 100 150 200 250
0
50
100
150
200
250
300
0 500 1000 1500 2000 2500 3000
Time, microseconds
OH
0
20
40
60
80
0 50 100 150 200 250
1542 K
1.42 atm
1486 K
1.52 atm 1377 K
1.54 atm
1343 K
1.61 atm
Literature model with data Improved model with data
Dames et al., 2013, Combust. Flame (data have uncertainty bars of  10 %)
Utilizing the synergy between experiments and theory for high-fidelity model development: shock
tube modeling of 3-pentanone oxidation
Defining reaction classes and making rate rules applicable to a wide range of compounds improves the
performance of computer-generated mechanisms. In the process, I’m also discovering new chemistry
not currently considered in models, which will play an important role in understanding the combustion
characteristics of future oxygenated alternative fuels.
400 ppm 3-
pentanone with
2800 ppm O2 in
Ar ( = 1.0).
High fidelity detailed kinetic models can be developed
in concert with high-quality experimental data. In this
case, 3-pentanone – a potential alternative fuel
surrogate – was studied behind reflected shock waves.
More post-shock concentration profiles were
measured for this species than have ever been
obtained for a single compound of this size. As a result,
the 46 species profiles of OH, H2O, CO, C2H4, CH3, and
3-pentanone were used to greatly improve the
‘foundational fuel chemistry’ of a previous model, as
illustrated by comparing the plots to the left.
105
106
107
108
109
1010
1011
1012
0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.20
1000 K / T
rate,s-1
102
103
104
105
106
107
0.01 0.1 1 10 100 1000
k,s-1
P, atm
Hippler et al. 20011
808 K
748 K
713 K
678 K
uncertainty bands
Oguchi et al. 20002
740 K
710 K
684 K
simulation results
From: Dames and Golden, JPCA, 2013
1Hippler, Striebel, Viskolcz, PCCP 2001
2Oguchi, Miyoshi, Koshi, Matsui, Bull. Chem. Soc. Jpn. 2000
 id A E
dt
   
rate of collisional production
of A at energy level j
collisional rate loss of
A at energy level i
-
rate loss of Ai
due to reaction
-
 
†
0exptotB
Btot
Qk T E
k T
k Th Q

   
 
 
 
 
††
,
,
r in
r in
W EQ
k E
Q h E

Master Equation Analysis and
RRKM theory
I’d like to develop models that take into account enhanced binding of
species due to electronic excited states accessible at high T, especially
for those with low singlet – triplet gaps, like this one below:
CH3O decomposition
1, 2
2, 2
3, 1
2, 3
3, 3





breaking bond k calculated with
energies obtained at
the M08SO/MG3S
level of theory and
benchmarked against
high level coupled
cluster theory
3
3
Energy
density
comparison
With up to 60% thermal
efficiencies, reactivity controlled
compression ignition engines rely
on two different fuels –
understanding their autoignition
characteristics is therefore critical
this new technology.
Methoxy/hydroxymethyl
potential energy surface