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MRD:wm814mrd

2017-05-26T04:56:57Z

Wm814:

== H+ H2 system ==
=== Dynamics from the Transition state region ===
The gradient of the potential surface at minimum and transition state are both zero. The minimum and transition state can be distinguished by second derivative. The minimum will have a positive value of second derivative. The transition state will have a negative second derivative.
[[File:WM814 TS Energy.JPG|200px|thumb|center|A Energy Curve Showing Gradient of Minimum and Transition state.]]
=== Trajectories form r1 =r2:locating the transition state ===
The estimated transition state position rts = 0.9077
At bond distance 0.9077, the internulear distance vs time diagram became a straight line, which means at that point, there was not vibration occur. Therefore transition state found.
[[File:wm814locatingr1r2.PNG|thumb|center|A Internuclear Distance vs time plot to find rts]]
===Trajector from r1 = rts+δ, r2=rts ===
The difference between MEP and dynamics is that MEP set the velocity to zero at every steps. The momentum A-B atoms under dynamics calculation approached 2.5 but never reached 2.5. The momentum of B-C atoms under dynamics calculation vibrated. However, under MEP calculation, the momentum stayed constant.
[[File:wm814r1+mep.PNG|200px|thumb|center|Internuclear Momenta r1+δ under MEP calculation.]]
[[File:wm814r1+dynamics.PNG|200px|thumb|center|Internuclear Momenta r1+δ under Dynamics calculation.]]
===Trajector from r1 = rts, r2+δ=rts ===
When set r2+0.01, the sign has reversed with the same value.
[[File:wm814r2+dynamics.PNG|200px|thumb|center|Internuclear Momenta r2+δ under dynamics calculation.]]
=== Reactive and Unreactive Trajectories ===
{| class="wikitable" border=1
!No.!! p1 !! p2!!if reactive!!description!!screenshots
|-
|1|| -1.25 || -2.5||Reactive||The system came in as a curve and passed through transition state then went out as a straight.||[[File:wm814reactive1.PNG|200px|thumb]]
|-
|2|| -1.5 || -2.0||Unreactive||The system did not pass transition state as the B-C bond got shorter than the distance of B-C bond increase thus not reactive.||[[File:wm814reactive2.PNG|200px|thumb]]
|-
|3|| -1.5 || -2.5||Reactive||The system passed through transition state and was vibrating in the whole process.||[[File:wm814reactive3.PNG|200px|thumb]]
|-
|4|| -2.5 || -5.0||Unreactive||The system passed transition state then bond distance increased thus no further reaction.||[[File:wm814reactive4.PNG|200px|thumb|]]
|-
|5|| -2.5 || -5.2||Reactive||The system passed transition state, then the bond distance fluctuated than the product formed||[[File:wm814reactive5.PNG|200px|thumb]]
|}
There are two assumption made in the transition state theory. The first one is that atoms obey Newton' s law of motion. The second one is that there is enough energy for the reaction to cross transition state after collision.

In this experiment, the collision angle is always 180 degrees, but in real life, this is not always. Thus the experiment results obtained in this lab is faster than real life experiment.
== F-H-H System ==
=== PES inspection ===
When B-C bond was shorter, the energy was approximately -103.8Kcal/mol, this is the F-H2 case. When A-B bond was shorter, the energy was approximately -133.6Kcal/mol, this is the H-HF case. The energy when from high to low in the reaction, therefore the reaction is exothermic. As the forward reaction was exothermic, the backward reaction mush be endothermic.
[[File:wm814exo.PNG|200px|thumb|center|An illustration of exothermic reaction]]
Forwards Reaction energy barrier: 103.8-103.3=0.5 kcal/mol

Backwards Reaction energy barrier: 133.6-103.3= 30.3 Kcal/mol
[[File:wm814exots.PNG|200px|thumb|center|An illustration of exothermic reaction transition state]]
=== Reaction Dynamics ===
==== F-H2 ====
When momentum between F-H was low (P=-0.5), changing the momentum of H-H do not dominate the results of reaction. i.e.sometimes reactive, sometime not. However, when the momentum of F-H was high (p=-0.8), even if the momentum of H-H was low (p=0.1), the reaction still occurred. From this, we can conclude that the momentum between H and F is what dominates the reaction.
[[File:wm8143.PNG|200px|thumb|left|Unreactive when PHF=-0.5, PHH=-1.28]]
[[File:wm8142.PNG|200px|thumb|right|Reactive when PHF=-0.8, PHH=0.1]]
[[File:wm8144.PNG|200px|thumb|centre|Reactive when PHF=-0.5, PHH=2.386]]

==== HF-H ====
When the momentum between H-F is high enough, no matter what values of H-H momentum, the reaction will still proceed. When the vibrational energy of H-F is high enough, the transnational energy of H does not matter. Therefor the momentum of H-F dominated the reaction
[[File:wm8146.PNG|thumb|left|Unreactive when PHF=-0.5, PHH=6]]
[[File:wm8147.PNG|thumb|right|Reactive when PHF=5.5, PHH=-0.5]]

File:Wm8147.PNG

2017-05-26T04:52:37Z

Wm814:

MRD:wm814mrd

2017-05-26T04:50:49Z

Wm814:

== H+ H2 system ==
=== Dynamics from the Transition state region ===
The gradient of the potential surface at minimum and transition state are both zero. The minimum and transition state can be distinguished by second derivative. The minimum will have a positive value of second derivative. The transition state will have a negative second derivative.
[[File:WM814 TS Energy.JPG|200px|thumb|center|A Energy Curve Showing Gradient of Minimum and Transition state.]]
=== Trajectories form r1 =r2:locating the transition state ===
The estimated transition state position rts = 0.9077
At bond distance 0.9077, the internulear distance vs time diagram became a straight line, which means at that point, there was not vibration occur. Therefore transition state found.
[[File:wm814locatingr1r2.PNG|thumb|center|A Internuclear Distance vs time plot to find rts]]
===Trajector from r1 = rts+δ, r2=rts ===
The difference between MEP and dynamics is that MEP set the velocity to zero at every steps. The momentum A-B atoms under dynamics calculation approached 2.5 but never reached 2.5. The momentum of B-C atoms under dynamics calculation vibrated. However, under MEP calculation, the momentum stayed constant.
[[File:wm814r1+mep.PNG|200px|thumb|center|Internuclear Momenta r1+δ under MEP calculation.]]
[[File:wm814r1+dynamics.PNG|200px|thumb|center|Internuclear Momenta r1+δ under Dynamics calculation.]]
===Trajector from r1 = rts, r2+δ=rts ===
When set r2+0.01, the sign has reversed with the same value.
[[File:wm814r2+dynamics.PNG|200px|thumb|center|Internuclear Momenta r2+δ under dynamics calculation.]]
=== Reactive and Unreactive Trajectories ===
{| class="wikitable" border=1
!No.!! p1 !! p2!!if reactive!!description!!screenshots
|-
|1|| -1.25 || -2.5||Reactive||The system came in as a curve and passed through transition state then went out as a straight.||[[File:wm814reactive1.PNG|200px|thumb]]
|-
|2|| -1.5 || -2.0||Unreactive||The system did not pass transition state as the B-C bond got shorter than the distance of B-C bond increase thus not reactive.||[[File:wm814reactive2.PNG|200px|thumb]]
|-
|3|| -1.5 || -2.5||Reactive||The system passed through transition state and was vibrating in the whole process.||[[File:wm814reactive3.PNG|200px|thumb]]
|-
|4|| -2.5 || -5.0||Unreactive||The system passed transition state then bond distance increased thus no further reaction.||[[File:wm814reactive4.PNG|200px|thumb|]]
|-
|5|| -2.5 || -5.2||Reactive||The system passed transition state, then the bond distance fluctuated than the product formed||[[File:wm814reactive5.PNG|200px|thumb]]
|}
There are two assumption made in the transition state theory. The first one is that atoms obey Newton' s law of motion. The second one is that there is enough energy for the reaction to cross transition state after collision.

In this experiment, the collision angle is always 180 degrees, but in real life, this is not always. Thus the experiment results obtained in this lab is faster than real life experiment.
== F-H-H System ==
=== PES inspection ===
When B-C bond was shorter, the energy was approximately -103.8Kcal/mol, this is the F-H2 case. When A-B bond was shorter, the energy was approximately -133.6Kcal/mol, this is the H-HF case. The energy when from high to low in the reaction, therefore the reaction is exothermic. As the forward reaction was exothermic, the backward reaction mush be endothermic.
[[File:wm814exo.PNG|200px|thumb|center|An illustration of exothermic reaction]]
Forwards Reaction energy barrier: 103.8-103.3=0.5 kcal/mol

Backwards Reaction energy barrier: 133.6-103.3= 30.3 Kcal/mol
[[File:wm814exots.PNG|200px|thumb|center|An illustration of exothermic reaction transition state]]
=== Reaction Dynamics ===
==== F-H2 ====
When momentum between F-H was low (P=-0.5), changing the momentum of H-H do not dominate the results of reaction. i.e.sometimes reactive, sometime not. However, when the momentum of F-H was high (p=-0.8), even if the momentum of H-H was low (p=0.1), the reaction still occurred. From this, we can conclude that the momentum between H and F is what dominates the reaction.
[[File:wm8143.PNG|200px|thumb|left|Unreactive when PHF=-0.5, PHH=-1.28]]
[[File:wm8142.PNG|200px|thumb|right|Reactive when PHF=-0.8, PHH=0.1]]
[[File:wm8144.PNG|200px|thumb|centre|Reactive when PHF=-0.5, PHH=2.386]]

==== HF-H ====
When the momentum between H-F is high enough, no matter what values of H-H momentum, the reaction will still proceed. therefor the momentum of H-F dominated the reaction
[[File:wm8146.PNG|200px|thumb|left|Unreactive when PHF=-0.5, PHH=6]]

File:Wm8146.PNG

2017-05-26T04:49:09Z

Wm814:

File:Wm8145.PNG

2017-05-26T04:44:44Z

Wm814:

File:Wm8144.PNG

2017-05-26T04:40:22Z

Wm814:

File:Wm8143.PNG

2017-05-26T04:37:51Z

Wm814:

File:Wm8142.PNG

2017-05-26T04:36:13Z

Wm814:

File:1.PNG

2017-05-26T04:30:58Z

Wm814: Wm814 uploaded a new version of File:1.PNG

File:Wm814exots.PNG

2017-05-26T04:15:58Z

Wm814:

File:Wm814exo.PNG

2017-05-26T04:07:02Z

Wm814:

MRD:wm814mrd

2017-05-26T03:49:49Z

Wm814:

File:Wm814reactive5.PNG

2017-05-26T03:48:02Z

Wm814:

File:Wm814reactive4.PNG

2017-05-26T03:46:47Z

Wm814:

File:Wm814reactive3.PNG

2017-05-26T03:43:58Z

Wm814:

File:Wm814reactive2.PNG

2017-05-26T03:40:58Z

Wm814:

File:Wm814reactive1.PNG

2017-05-26T03:38:03Z

Wm814:

File:Wm814r2+dynamics.PNG

2017-05-26T03:27:26Z

Wm814:

File:Wm814r1+dynamics.PNG

2017-05-26T03:10:18Z

Wm814:

File:Wm814r1+mep.PNG

2017-05-26T03:09:43Z

Wm814:

MRD:wm814mrd

2017-05-26T03:03:39Z

Wm814:

File:Wm814locatingr1r22.PNG

2017-05-26T02:20:30Z

Wm814:

File:Wm814locatingr1r2.PNG

2017-05-26T02:19:57Z

Wm814:

MRD:wm814mrd

2017-05-26T02:07:49Z

Wm814: /* Dynamics from the Transition state region */

== H+ H1 system ==
=== Dynamics from the Transition state region ===
The gradient of the potential surface at minimum and transition state are both zero. The minimum and transition state can be distinguished by second derivative. The minimum will have a positive value of second derivative. The transition state will have a negative second derivative.
[[File:WM814 TS Energy.JPG|200px|thumb|center|A Energy Curve Showing Gradient of Minimum and Transition state.]]

MRD:wm814mrd

2017-05-26T02:04:01Z

Wm814: Created page with "== H+ H1 system == === Dynamics from the Transition state region === The gradient of the potential surface at minimum and transition state are both zero. The minimu..."

== H+ H1 system ==
=== Dynamics from the Transition state region ===
The gradient of the potential surface at minimum and transition state are both zero. The minimum and transition state can be distinguished by second derivative. The minimum will have a positive value of second derivative. The transition state will have a negative second derivative.
[[File:WM814 TS Energy.jpg|200px|thumb|center|A Energy Curve Showing Gradient of Minimum and Transition state.]]

File:WM814 TS Energy.JPG

2017-05-26T02:00:21Z

Wm814: Wm814 uploaded a new version of File:WM814 TS Energy.JPG

File:WM814 TS Energy.JPG

2017-05-26T01:47:59Z

Wm814: