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THE ROLE OF CRYSTALLINE ENVIRONMENT IN THE
INTRAMOLECULAR REACTIONS
Elena V. Boldyreva
REC-008 MDEST
Novosibirsk State University & Institute of Solid State Chemistry RAS
Introduction
Effects of the environment Response of the environment
Conclusions
Introduction
Effects of the environment Response of the environment
Conclusions
Supramolecular systems
Supermolecules Supramolecular assemblies
Associates(dimers)
Very large molecules(proteins, DNA, RNA) solutions crystals
Supermolecules(Multisubunit proteins,
nucleoproteids)
Associates of supermolecules
Supramolecular assemblies of supermolecules (protein crystals)
Supramolecular systems
Supermolecules Supramolecular assemblies
Associates(dimers)
Very large molecules(proteins, DNA, RNA) solutions crystals
Supermolecules(Multisubunit proteins,
nucleoproteids)
Associates of supermolecules
Supramolecular assemblies of supermolecules (protein crystals)
Molecular / ionic-molecular crystals
• Van der Waals interactions
• Hydrogen bonds
• Other specific interactions
on the structures of assemblies
on the properties of assemblies
supramolecular synthesis crystal engineering statistical analyses of databases prediction of crystal structures
physical properties
chemical reactivity
important for practice intermolecular potentials
response to external actions
The effect of intermolecular interactions
molecular crystal kinetics reaction selectivity
effects of
reaction type
structures of product
temperaturewavelengthpressure
(homogeneous/heterogeneous, single-crystal single-crystal) cooperative effects
on the structures of assemblies
on the properties of assemblies
supramolecular synthesis crystal engineering statistical analyses of databases prediction of crystal structures
physical properties
chemical reactivity
important for practice intermolecular potentials
response to external actions
The effect of intermolecular interactions
molecular crystal kinetics reaction selectivity
effects of
reaction type
structures of product
temperaturewavelengthpressure
(homogeneous/heterogeneous, single-crystal single-crystal) cooperative effects
on the structures of assemblies
on the properties of assemblies
supramolecular synthesis crystal engineering statistical analyses of databases prediction of crystal structures
physical properties
chemical reactivity
important for practice intermolecular potentials
response to external actions
The effect of intermolecular interactions
molecular crystal kinetics reaction selectivity
effects of
reaction type
structures of product
temperaturewavelengthpressure
(homogeneous/heterogeneous, single-crystal single-crystal) cooperative effects
on the structures of assemblies
on the properties of assemblies
supramolecular synthesis crystal engineering statistical analyses of databases prediction of crystal structures
physical properties
chemical reactivity
important for practice intermolecular potentials
response to external actions
The effect of intermolecular interactions
molecular crystal kinetics reaction selectivity
effects of
reaction type
structures of product
temperaturewavelengthpressure
(homogeneous/heterogeneous, single-crystal single-crystal) cooperative effects
on the structures of assemblies
on the properties of assemblies
supramolecular synthesis crystal engineering statistical analyses of databases prediction of crystal structures
physical properties
chemical reactivity
important for practice intermolecular potentials
response to external actions
The effect of intermolecular interactions
molecular crystal kinetics reaction selectivity
effects of
reaction type
structures of product
temperaturewavelengthpressure
(homogeneous/heterogeneous, single-crystal single-crystal) cooperative effects
Effects of environment
• Steric restrictions• Interactions in the
second coordination sphere
• Cooperative phenomena
• Passive reaction cavity• Active reaction cavity• Flexible reaction
cavity • Feed-back phenomena
n'
n
Two groups of problems:
• Effect of the environment on the reaction rate and the very possibility of the reaction
• Response of the environment to the reaction
Introduction
Effects of the environment Response of the environment
Conclusions
Variation of the environment
• Various outersphere anions
• Different polymorphs
• Continuous distortion of the structure (variable pressure / elastic deformation)
PowderCell 2 .0
[Co(NH3)5NO2]Cl2
[Co(NH3)5NO2]Cl(NO3)
a
(a’) c0
(a’)
[Co(NH3)5NO2]I2, Pnma
[Co(NH3)5NO2]I2, C2/m
Effects of the environment:
• Changes in the mechanism
• Different reaction products (or no reaction at all in particular environments)
• Kinetics
• Spatial propagation (homogeneous / heterogeneous)
• Single crystal single crystal / Fragmentation of crystals
Effects of the environment:
• Changes in the mechanism
• Different reaction products (or no reaction at all in particular environments)
• Kinetics
• Spatial propagation (homogeneous / heterogeneous)
• Single crystal single crystal / Fragmentation of crystals
Linkage isomerization in [Co(NH3)5NCS]Cl2
Solution: intramolecular; crystal: intermolecular
Effects of the environment:
• Changes in the mechanism
• Different reaction products (or no reaction at all in particular environments)
• Kinetics
• Spatial propagation (homogeneous / heterogeneous)
• Single crystal single crystal / Fragmentation of crystals
[Co(NH3)5ONO]An [Co(NH3)5NO2]An
An = 2Cl-, 2Br-, 2I-, 2F-, Cl-(NO3)-, 2(NO3)-, (SO4)2-, etc. 100% linkage isomerization
<->
h
T
Linkage isomerization in [Co(NH3)5NO2]An (intramolecular)
Solution:
Crystals:
An = (C2O4)2- no photoisomerization, 100% red-ox decomposition
An = (SiF6 )2- photoisomerization not complete (40%), no red-ox decomposition
75% red-ox decomposition + 25% linkage isomerization
Effects of the environment:
• Changes in the mechanism
• Different reaction products (or no reaction at all in particular environments)
• Kinetics
• Spatial propagation (homogeneous / heterogeneous)
• Single crystal single crystal / Fragmentation of crystals
Different outersphere species
Racemization of (+)-[Co(en)3]X3
0 50 100 150 200 t, h0.0
0.2
0.4
0.6
Cl-
SCN-
Br-
I-
Linkage isomerization in [Co(NH3)5ONO]An
0 1 2 3 4 5 6 7 80
20
40
60
80
100 1
32
4
% O
NO
t, ч.
0 10000 20000 30000 400000,0
0,2
0,4
0,6
0,8
1,0
4
5
32
1
A(t
)/A
(0)
t, сек
«Free space» around the nitro-ligandin [Co(NH3)5NO2]XY
XY = 2Cl- XY = 2Br- XY = Cl-(NO3)-
XY = 2I- XY = (SiF6)2- XY = (C2O4)2-
Different polymorphs
0 2000 4000 6000 8000 10000 12000 140000
1
2
3
4
5
6
2
1
-ln
(1-
)
t, сек
0 5000 10000 150000
1
2
3
4
5
6
2
1
-ln
(1-
)
t, сек
0 5000 10000 150000
1
2
3
4
5
6
3
2
1
-ln(1
-)
t, сек
[Co(NH3)5ONO]Cl2
[Co(NH3)5ONO]Br2
[Co(NH3)5ONO]I2
Isomerization in the different polymorphs
12
1
2
1
3
2
Continuous distortionof the same structure(hydrostatic pressure)
Effect of hydrostatic pressure on the linkage isomerization
[Co(NH3)5ONO]Br2 [Co(NH3)5NO2]Br2k1
k2
V > 0 (!)
but
V# < 0
Pressure accelerates
the reaction (!)
Effect of hydrostatic pressure on the linkage isomerization
[Co(NH3)5ONO]Br2 [Co(NH3)5NO2]Br2k1
k2
V > 0 (!)
but
V# < 0
Pressure accelerates
the reaction (!)
Effects of the environment:
• Changes in the mechanism
• Different reaction products (or no reaction at all in particular environments)
• Kinetics
• Spatial propagation (homogeneous / heterogeneous)
• Single crystal single crystal / Fragmentation of crystals
Effects of the environment:
• Changes in the mechanism
• Different reaction products (or no reaction at all in particular environments)
• Kinetics
• Spatial propagation (homogeneous / heterogeneous)
• Single crystal single crystal / Fragmentation of crystals
Linkage isomerization in [Co(NH3)5NO2]Cl(NO3)
Continuous distortionof the same structure
(elastic bending)
Variation of the environment
holder
crystal
mirror
load laser
scale
light
121086420
700
600
500
400
300
200
100
0
21Zm
Z=wt
t, min
0.30.20.10.0
0.9
0.8
0.7
0.6W
/W0
L/L,%
FR
AC
TU
RE
Effect of elastic bending on the linkage isomerization
[Co(NH3)5NO2]Cl(NO3) [Co(NH3)5ONO]Cl(NO3)
V < 0 (!)
but
V# > 0
Quantum yielddecreases (!) in the
elastically compressed parts of the crystals
h
Effect of elastic bending on the linkage isomerization
[Co(NH3)5NO2]Cl(NO3) [Co(NH3)5ONO]Cl(NO3)
V < 0 (!)
but
V# > 0
Quantum yielddecreases (!) in the
elastically compressed parts of the crystals
h
Introduction
Effects of the environment Response of the environment
Conclusions
Effects of the environment:
• Changes in the mechanism
• Different reaction products (or no reaction at all in particular environments)
• Kinetics
• Spatial propagation (homogeneous / heterogeneous)
• Single crystal -> single crystal / Fragmentation of crystals
Response of the environment:
Changes in the mechanism
Different reaction products (or no reaction at all in particular environments)
Kinetics
Spatial propagation (homogeneous / heterogeneous)
Single crystal single crystal / Fragmentation of crystals
Response:
Macroscopic level
• Bending• Fragmentation
Microscopic level
• Changes in the interatomic distances
• Shifts in the
vibrational spectra
Lattice strain
Response:
Macroscopic level
• Bending• Fragmentation
Microscopic level
• Changes in the interatomic distances
• Shifts in the
vibrational spectra
Lattice strain
Linear strain induced by [Co(NH3)5NO2]XY [Co(NH3)5ONO]XY linkage isomerization
XY
2Cl- 2Br- 2I- (в Pnma) Cl-(NO3)- 2(NO3)
-
a/a(%) +0.13(4) +0.94(7) 0.0 -2.34(5) -1.47(8)
b/b(%) +2.0(1) +1.37(5) -1.2(1) -1.8(1) -1.47(8)
c/c(%) -3.42(5) -3.47(5) -0.92(8) +3.51(7) +2.56(5)
( ) -4.78(2) -4.52(3) - - -
V/V(%) -0.95(6) -0.84(6) -2.1(2) -0.7(1) -0.4(1)
l1/l1(%) +3.01(2) +3.38(4) 0.0 +3.51(7) +2.56(5)
l2/l2(%) +1.99(2) +1.37(2) -0.92(8) -1.8(1) -1.47(8)
l3/l3(%) -5.96(2) -5.59(3) -1.2(1) -2.34(5) -1.47(8)
Lattice strain in [Co(NH3)5NO2]Cl(NO3)
Hydrostaticpressure
Nitro - nitrito linkagephotoisomerization
Linear strain in directions of atom-atom contacts in the structure of [Co(NH3)5NO2]Cl(NO3)
Nitro - nitrito linkagephotoisomerization
Hydrostaticpressure
Effect of elastic bending on the linkage isomerization
[Co(NH3)5NO2]Cl(NO3) [Co(NH3)5ONO]Cl(NO3)
V < 0 (!)
but
V# > 0
Quantum yielddecreases (!) in the
elastically compressed parts of the crystals
h
0 10 20 30 40 50 60 70 801026
1028
1030
1032
1034
V, A
3
t, ч
0 1 2 3 4 5900
950
1000
V, A
3
P, ГПa
0 10 20 30 40 50 60 70 8010,410,510,610,710,810,911,011,111,2
a
c
a&c,
At, ч
0 1 2 3 4 510,010,110,210,310,410,510,610,710,8
a
ca&c,
A
P, ГПа
0 10 20 30 40 50 60 70 808,7
8,8
8,9
9,0
9,1
b, A
t, ч
0 1 2 3 4 58,6
8,7
8,8
8,9
9,0
b, A
P, ГПа
[Co(NH3)5ONO]Br2
Nitrito-nitro linkage thermal isomerization
Hydrostatic pressure
Effect of hydrostatic pressure on the linkage isomerization
[Co(NH3)5ONO]Br2 [Co(NH3)5NO2]Br2k1
k2
V > 0 (!)
but
V# < 0
Pressure accelerates
the reaction (!)
Introduction
Effects of the environment Response of the environment
Conclusions
“Реакция неотделима от среды,
в которой она протекает”
Н. Меншуткин, 1890 г.
“A reaction cannot be separated
from the medium”
N. Menschutkin, 1890 г.
Medium = Environment
• Solvent
• Cages of various types
• Crystalline environment in molecular crystals