Rep:Mod:JakeHootonProject IonicLiquids

This project concerns the optimisation and analysis of organic cations (-onium ions) of the sort which might be used in an ionic liquid solvent.

-onium ions

Originally, NMe₄⁺ was optimised immediately with the 6-31G(d)(p) basis set and then submitted for frequency analysis. When similar calculations were tried for PMe₄⁺ and SMe₃⁺, the calculations were taking too long and it was decided that 6-31G(d)(p) was not a suitable starting basis set. PMe₄⁺ was then optimised with the pseudo-potential basis set LANL2DZ, however I was advised this was not the correct procedure for the project. I then decided that, in order to save time, a simple optimisation with the 3-21G basis set would be necessary for each of these molecules, before higher-level 6-31G(d)(p) optimisations.

The ions PMe₄⁺, and SMe₃⁺, were constructed in Gaussview, first optimised with the 3-21G basis set (DFT, B3LYP), then further optimised with the 6-31G(d)(p) basis set, and finally submitted for a frequency calculation. For the frequency calculations, by observing the item tables, it was found for SMe₃⁺ that the maximum displacement had not converged, and for PMe₄⁺ that neither the maximum displacement nor the RMS displacement had converged. Therefore the 6-31G(d)(p) calculations were refined and repeated. The original log files from the 3-21G calculations were optimised again with the 6-31G(d)(p) basis set, this time with the keywords int=ultrafine and scf=conver=9. These files were then submitted for frequency calculations; for SMe₃⁺ this strategy worked and everything had converged even in the frequency calculation log file, however for PMe₄⁺ the maximum displacement had still not converged. I then optimised PMe₄⁺ again with the additional opt=tight keyword, the calculation took 1hr 18min and then failed - Gaussian showed the warning message 'Link Died!'. During this time I also sought help from Tricia Hunt; I learned from her that for frequency analysis calculations, only the top two (force) criteria of the item table were of absolute importance concerning convergence, not the lower two (displacement) criteria. Therefore I could continue with the project and compare results. The calculations for NMe₄⁺ were then repeated in a similar fashion to the PMe₄⁺ and SMe₃⁺ molecules, so that the calculations were comparable. Omitting the 3-21G optimisations, the 6-31G(d)(p) optimisations with keywords, and the following frequency calculations are shown below.

Another point of note is that originally, the SMe₃⁺ calculations failed mid-calculation, with Gaussian reporting an error ("Link Died!"). This was probably due to the fact that, since Gaussview did not provide an 'all-single-bond' trigonal planar fragment for the sulphur atom, I had built and edited the molecule around the trigonal planar BH₃ fragment. Boron is a smaller atom than sulphur and therefore the starting bond lengths will have been much too small. I then built and edited the molecule about a trigonal planar phosphorus fragment - phosphorous is an atom similar in size to sulphur and therefore the starting bond lengths will have been more accurate lengths from which to start an optimisation. Indeed with the repeated calculation, the optimisation proceeded without problems.

A charge of +1 and a singlet spin state were applied to each of these molecules before the calculations.

NMe₄⁺

Optimisation

Log file: Media:JAKEHOOTON_NME4_OPT_631GDP_ULTRAFINE_SCFCONVER9.LOG‎

Results Summary:

Item Table:

Item Value Threshold Converged?
Maximum Force 0.000019 0.000450 YES
RMS Force 0.000006 0.000300 YES
Maximum Displacement 0.000948 0.001800 YES
RMS Displacement 0.000235 0.001200 YES
Predicted change in Energy=-1.234870D-08
Optimization completed.
-- Stationary point found.

Frequency

Log file: Media:JAKEHOOTON_NME4_FREQ_631GDP_ULTRAFINE_SCFCONVER9.LOG‎

Results Summary:

Item Table:

 Item Value Threshold Converged?
Maximum Force 0.000017 0.000450 YES
RMS Force 0.000008 0.000300 YES
Maximum Displacement 0.001034 0.001800 YES
RMS Displacement 0.000367 0.001200 YES
Predicted change in Energy=-1.773474D-08
Optimization completed.
-- Stationary point found.

Low Frequencies:

Low frequencies --- -5.8426 -0.0009 -0.0004 0.0006 4.7330 5.2553
Low frequencies --- 183.5025 288.6984 289.1320

PMe₄⁺

Optimisation

Log file: Media:JAKEHOOTON_PME4_OPT_631GDP_ULTRAFINE_SCFCONVER9.LOG‎

Results Summary:

Item Table:

 Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000017 0.000300 YES
Maximum Displacement 0.001128 0.001800 YES
RMS Displacement 0.000415 0.001200 YES
Predicted change in Energy=-7.378108D-08
Optimization completed.
-- Stationary point found.

Frequency

Log file: Media:JAKEHOOTON_PME4_FREQ_631GDP_ULTRAFINE_SCFCONVER9.LOG‎

Results Summary:

Item Table:

Item Value Threshold Converged?
Maximum Force 0.000030 0.000450 YES
RMS Force 0.000015 0.000300 YES
Maximum Displacement 0.002107 0.001800 NO
RMS Displacement 0.000856 0.001200 YES
Predicted change in Energy=-8.400439D-08

Low Frequencies:

Low frequencies --- -2.3169 -0.0024 -0.0016 -0.0011 7.3269 17.1786
Low frequencies --- 156.8757 192.1795 192.4230

SMe₃⁺

Optimisation

Log file: Media:JAKEHOOTON_SME3_OPT_631GDP_ULTRAFINE_SCFCONVER9.LOG‎

Results Summary:

Item Table:

 Item Value Threshold Converged?
Maximum Force 0.000013 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000876 0.001800 YES
RMS Displacement 0.000307 0.001200 YES
Predicted change in Energy=-6.083938D-09
Optimization completed.
-- Stationary point found.

Frequency

Log file: Media:JAKEHOOTON_SME3_FREQ_631GDP_ULTRAFINE_SCFCONVER9.LOG‎

Results Summary:

Item Table:

Item Value Threshold Converged?
Maximum Force 0.000013 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.001220 0.001800 YES
RMS Displacement 0.000503 0.001200 YES
Predicted change in Energy=-1.101742D-08
Optimization completed.
-- Stationary point found.

Low Frequencies:

Low frequencies --- -9.4139 -3.5890 -0.0042 -0.0042 0.0022 3.4324
Low frequencies --- 162.1354 199.5415 199.7929

Comparison of Structures

caption

Compound	C-(Central Atom)-C Bond Angle / °	C-(Central Atom) Bond Length / Å	H-C-H Bond Angle / °	C-H Bond Length / Å	H-C-(Central Atom) Bond Angle / °
NMe4+	109.5	1.53	110.4	1.09	110.4
PMe4+	109.5	1.87	109.7	1.09	109.3
SMe3+	100.5	1.91	110.9 (for six H facing LP)	1.09	106.2 (for six H facing LP)
			112.3 (for 3 H pointing away from LP)		108.7 (for 3H pointing away from LP)

The tetramethylammonium and tetramethylphosphonium ions are both tetrahedral about the central heteroatom, whereas the SMe₃⁺ ion has a trigonal pyramidal structure due to the presence of a lone pair around sulphur (sulphur is group 16 whereas P and N are group 15, therefore sulphur has one more electron and forms alkyl cations with one fewer R group and lone pair in its structure - the shapes are described here according to VSEPR theory). This is shown in the first column of the table, where the C-(Central Atom)-C bond angle is the typical tetrahedral angle (109.5°) for NMe₄⁺ and PMe₄⁺, but only 100.5° for SMe₃⁺ - the 'pseudo-tetrahedral' angles between S-Me bonds are reduced slightly by repulsion from the LP, which occupies the final tetrahedral position. The LP-S-Me angles are correspondingly slightly larger.

A marked difference is visible in the C-(Central Atom) bond lengths from N -> P; this is well rationalised by drawing parallels with the trends in atomic radii in the periodic table. Atomic radii generally increase down a group (i.e. from N to P) due to electron shielding effects - P has one more full shell of electrons with the same principal atomic number, below its valence electrons, than does nitrogen. These shield the increased nuclear charge, so that with P, the valence electrons (on average) sit considerably further from the nucleus than in N. The increase in this bond length between the P-compound and the S-compound is much less pronounced. In fact, going by the previous argument, an increase is contrary to what we would expect since atomic radii typically decrease across a period (electrons added to the same valence shell are poor at shielding and do little to counter the increased nuclear charge). However, this change is small and a similar bond length would be what we would expect.

The methyl C-H bond lengths (fourth data column above) are all essentially the same between each compound - suggesting that the different central heteroatoms have no effect on this bond length. However, when considering the methyl H-C-H bond angles, some slight changes do become obvious. Whereas for the N-compound and the P-compound the groups around each carbon are all essentially unaltered from a tetrahedral arrangement, the arrangement is changed in the S-compound. Due to its overall trigonal bipyramidal structure, in the optimised conformation there are 2 hydrogens on each methyl group which face the lone pair, and one which points away. For the hydrogens which point away, the bond H_{point away}-C-H_{face LP} bond angle is almost 2 degrees larger than the H_{face LP}-C-H_{face LP} bond angle. Similarly the H_{point away}-C-(Central atom) bond angles are almost 2 degrees larger than the H_{face LP}-C-(Central atom) bond lengths. This is hard to explain geometrically - it suggests that the 'point away' hydrogens are pushed away slightly from the molecule's principal axis of symmetry (within the 'closed' face - opposite the LP), however examination of the intramolecular distance between each of these 'point away' hydrogens shows them to be 2.65 Å, which would typically indicate attraction through Van der Waals/London dispersion forces. What is obvious though is that all the hydrogens on each methyl group in the S-compound sit slightly closer to the central atom and slighly further away from each other (in terms of bond angles) than in the N- and P-compounds.

MO Analysis

The optimised -onium ions were then submitted for a full NBO and MO analysis. The results are presented below.

NMe₄⁺

Log file: Media:JAKEHOOTON_NME4_NBO_631GDP_POPFULL.LOG‎

Results Summary:

MO Analysis

I have chosen to animate 7 MOs since in order to give a better illustration of bonding in this molecule.

Pictures of the MOs

MO number	MO Picture	Description
6		This MO is the first non-core MO of the tetramethyl ammonium ion. It is totally symmetric, is comprised of just one phase with no nodes, and covers all the space within the molecule where we would normally consider there to be 'bonds' (between the atoms).
8		This is a low energy, highly bonding MO which I thought it was worth highlighting, since it shows an interesting structure. This MO is composed of two separate phases with a single node in the middle - the node sits on the nitrogen atom. Each phase of this MO is strongly bonding between the two N-Me 'bonds' and each of the six C-H (methyl) 'bonds' within that phase of the MO. However, each of these phases also shows bonding interactions between the two methyl groups it envelops - so called 'through-space' interaction. If we consider the green lobe of the orbital (shown on the left) then these through-space interactions are between the 'top' and the 'right' methyl groups in the picture. Generally these through-space interactions are weaker interactions - this can be seen by the slight dip in the density of each lobe of this MO (curvature on the depicted surface) between its methyl groups in question. For this entire MO though, the through-space interactions have made a significant contribution to its overall structure. This MO highlights the fact that there is some delocalisation across the entire molecule.
10		This MO is also deep in energy. It would still be considered a bonding MO overall, however it also shows significant antibonding interactions. The bonding interactions here are within each separate methyl group, each of which has its own lobe of the MO, each with the same phase. Each of these lobes occupies space between the atoms, giving the MO some bonding character. The anti-bonding interactions are between the central nitrogen with each methyl group - the nitrogen atom is surrounded by its own lobe of the molecular orbital (with opposite phase to the methyl lobes) and there is a radial node (or four nodes if considered separately) between this lobe and the surrounding methyl lobes. This node occupies a space directly between the N and the C atoms, giving strong anti-bonding character. In contrast to the previous MO, through-space interactions have a much lesser effect here and the bonding interaction is more localised (specifically within particular methyl groups, not between them across the molecule).
11		Orbitals 11 is interesting because it shows both localised and delocalised bonding interactions, and also antibonding interactions. The central red lobe of this MO is highly delocalised. It covers directly the space between one of the N-C 'bonds' and could therefore be called bonding between these two nuclei, however this lobe also extends to cover six protons, two each from three methyl groups in the molecule. The lobe could also be considered to have bonding character across these six C-H 'bonds' however its high delocalisation spreads the electrons across the molecule, and at a push it could also be considered non-bonding. The case is similar for the green lobes - the one on the right of this picture envelops one of the methyl groups (similar to the green lobes in orbital 10) and could be considered to have bonding character here, despite showing a small degree of delocalisation across the CH3 unit. The other green lobe, on the left, is delocalised over the three remaining protons from the first three methyl groups that were discussed. The delocalisation is due to through space interactions and again this lobe could be said to have both bonding and non-bonding character. However, since all of the nodes in this MO sit on particular atoms, rather than in between them, MO 11 has no obvious antibonding character and it can be said to be bonding overall. N.B. This high degree of delocalisation is the case for most of the filled orbitals below the HOMO. In particular, orbitals which show bonding character across the central part of the molecule (the official N-C bonds) also all show a high degree of delocalisation, in particular orbitals 7, 9, 12 and 13 (both the same shape as orbital 11 but orientated differently about the atoms), 19, and 20.
21 HOMO		Orbital 21 is the HOMO. Again, it shows both bonding and antibonding interactions. Of particular interest are the two smaller lobes in the middle of the orbital (one red and one green), since they each comprise wholly of a bonding interaction between one N and C atom - this is the first MO which shows such behaviour without delocalisation across the outer atoms. The remaining, larger, outer lobes can again be said to be bonding across the official C-H 'bonds' which they cover, yet these lobes are again delocalised due to the (weaker) through space interactions, stemming originally from the H atomic orbitals. It is particularly obvious here by looking at the curvature of the lobes that the through space interactions are weak (the drawn surface of the outer lobes gets very thin between the methyl groups!). Again, the nodes in this orbital sit on atoms rather than between them, and the HOMO can be said to have bonding character overall.
22 LUMO		Orbital 22 is the LUMO and suddenly the character of this MO has immediately become highly antibonding - none of the space occupied by the lobes of the LUMO sits between atoms which have formal 'bonds'. There are four small (roughly spherical) red lobes which sit outside the terminal methyl groups of the molecule. Between these lobes and the centre of the molecule the is a large green lobe which again occupies all of the non-bonding space between the methyl protons and is antibonding. Next, between this large lobe and the centre of the molecule, there is a radial node between the central Nitrogen and surrounding C carbons (where the official 'bonds' are) and upon close inspection it can be seen that the Nitrogen itself is surrounded by its own, opposite phase, red lobe. There are five nodes in total (the radial one in the middle and four on the outside, sitting on the methyl carbons between the green and the separate red lobes). All of these features combine to give the LUMO highly antibonding character.
56		Orbital 56 is one of the very-high energy antibonding orbitals above the LUMO, which are not normally considered. It is included here to illustrate the highly antibonding character and often strange appearance of such orbitals. Here, each separate methyl proton and the central nitrogen are surrounded by their own 'red-phase' lobes, which very much resemble s-atomic orbitals and were originally derived from such orbitals. Filling the space between these lobes (yet still not where the official 'bonds' are) is an opposite phase (green) lobe. There are thirteen nodes present here, one radial node between the central (red) Nitrogen lobe and the green lobe, and twelve more separate each proton (red) lobe from the large green lobe. These nodes occupy every position where the official 'bonds' would be, therefore giving this MO extreme antibonding character.

PMe₄⁺

MO and NBO calculation log file: Media:JAKEHOOTON_PME4_NBO_631GDP_POPFULL.LOG‎

Results Summary:

SMe₃⁺

MO and NBO calculation log file: Media:JAKEHOOTON_SME3_NBO_631GDP_POPFULL.LOG‎

Results Summary:

Comparison of NBO analysis between the three ions

Tabulated numerical values for the charge distribution

Below, the numerical values for the charge distributions across these atoms are given in a table, in terms of the elementary charge, e = 1.60×10−19 C. A visual representation is provided under the following subheading.

caption

Type of nucleus	NMe4+	PMe4+	SMe3+
Central Atom	-0.295 (N)	+1.667 (P)	+0.917 (S)
Carbon	-0.483	-1.060	-0.846
Hydrogen	+0.269	+0.289	+0.279

Comment:

The formal picture for bonding in a tetraalkyl ammonium ion.

The results here show data that for NMe₄⁺ is initially surprising - the central nitrogen atom harbours a negative charge, not a positive one. This is different from the formal, well known picture of the bonding in such ammonium ions, shown in the picture the right. In the formal picture, the tetraalkylammonium ion is built from a trialkyl ammonia molecule donating its lone pair of electrons to a hypothetical "R⁺" molecular fragment, therefore forming a dative covalent bond (shown in the picture by a bond with an arrowhead) and leaving a formal (single) positive charge residing on the Nitrogen.

The NBO charge distribution analysis shows that in actual fact both the nitrogen and the four methyl carbons stabilise some negative charge (more so on the carbons than the nitrogen) and that the positive charge on this ion resides with the the twelve methyl hydrogens on the outer part of the molecule.

Upon further consideration, this picture seems entirely sensible, since the MOs which were analysed earlier showed a high degree of delocalisation across the molecule, spreading the electron density around. It should also be considered that nitrogen is a highly electronegative element, and hydrogen is highly electropositive with respect to carbon, therefore nitrogen would naturally harbour the negative charge and hydrogen the positive charge. Therefore, it can be concluded that the formal picture of the bonding in the tetramethyl ammonium ion is inadequate for this level of analysis, since it has given wrong information. The computational analysis has revealed the true picture!

Bearing in mind this information with respect to this ion's use in ionic liquids, the situation is good, since positive charge spread around the large outer surface of the cation is what is needed to form an ionic liquid at room temperature - bulky delocalised cations which lead to a weaker interaction with their anion counterparts.

Tabulated visual representations of the charge distribution

Below, visual representations are provided in a table to show the charge distribution across each molecule. The first row shows the charge distributions within a range suitable for each molecule, ideal for visualising the charge distribution between individual atoms. The second row shows pictures with the colour range of charge distributions normalised the compound with the largest boundaries, i.e. PMe₄⁺, ±1.667 e. These pictures are provided in order to better visualise the differences in overall charge distribution across each molecule.

caption

Description of charge distribution	NMe4+	PMe4+	SMe3+
Default for the molcule: ............... ±0.483 for NMe4+, ±1.667 for PMe4+, and ±0.917 for SMe3+
*****	*****	*****	*****
Adjusted or 'normalised' for visual comparison: ............. ±1.667 for all molecules

Further Comment: By observing both the numerical values and the visualisations for the charge distributions, comparisons can be made between these three cations. The first thing to note is that for all three cations, the twelve outer methyl protons harbour approximately the same level of positive charge density (approximately +2.8 e). Differences arise when the distribution of charge across the central atom and methyl carbons in the inner part of the molecules is considered. The most highly polarised structure is that of the PMe₄⁺ molecule, which stabilises a high magnitude of positive charge (+1.7 e) on the central P atom and a similar magnitude of negative charge on the methyl carbons (+1.1 e). For SMe₃⁺, the qualitative distribution is similar but, lesser in magnitude (+0.9 e on sulphur and -0.8 e on the methyl carbons). In high contrast and as discussed earlier, the qualitative charge distribution on NMe₄⁺ is different, with negative charge stabilised both the central atom and methyl carbons. The magnitude of polarisation of charge across NMe₄⁺ is also very low compared with that across the PMe₄⁺ and SMe₃⁺ cations, which is obvious from the 'normalised' charge distributions on the second row of the visualisations table - the distribution is almost non-existent compared with that across the PMe₄⁺ ion!

The difference in qualitative structure is rationalised by considering nitrogen's high Pauling electronegativity (3.04) with respect to phosphorus (2.19) and sulphur (2.58). The quantitative differences between the amount of positive charge stabilised on phosphorus and sulphur can again be rationalised by considering that phosphorus (2.19) is more electropositive than sulphur (2.58)(and the MOs for these structures are highly delocalised, allowing much electron movement).

Contributions of the C and heteroatom to the C-X bond

N-C

4. (1.98452) BD ( 1) C 1 - N 17
( 33.65%) 0.5801* C 1 s( 20.78%)p 3.81( 79.06%)d 0.01( 0.16%)
0.0003 0.4552 -0.0237 0.0026 -0.7024
-0.0298 0.2338 0.0099 0.4910 0.0208
-0.0146 -0.0307 0.0102 0.0195 -0.0017
( 66.35%) 0.8146* N 17 s( 25.00%)p 3.00( 74.97%)d 0.00( 0.03%)
0.0000 0.5000 -0.0007 0.0000 0.6846
-0.0001 -0.2279 0.0000 -0.4786 0.0001
-0.0064 -0.0135 0.0045 0.0086 -0.0007

P-C

4. (1.98031) BD ( 1) C 1 - P 17
( 59.58%) 0.7719* C 1 s( 25.24%)p 2.96( 74.68%)d 0.00( 0.08%)
-0.0002 -0.5021 -0.0171 0.0020 0.6229
-0.0114 0.5203 -0.0095 0.2962 -0.0054
-0.0218 -0.0124 -0.0104 -0.0040 0.0094
( 40.42%) 0.6358* P 17 s( 25.00%)p 2.97( 74.15%)d 0.03( 0.85%)
0.0000 -0.0001 -0.5000 0.0008 0.0000
0.0000 -0.6208 0.0009 0.0000 -0.5185
0.0007 0.0000 -0.2952 0.0004 -0.0694
-0.0395 -0.0330 -0.0126 0.0299

S-C

4. (1.98631) BD ( 1) C 1 - S 13
( 48.67%) 0.6976* C 1 s( 19.71%)p 4.07( 80.16%)d 0.01( 0.14%)
-0.0003 -0.4437 -0.0140 0.0033 0.7072
-0.0055 -0.4114 0.0032 0.3634 0.0098
0.0231 -0.0208 0.0121 -0.0131 0.0096
( 51.33%) 0.7164* S 13 s( 16.95%)p 4.86( 82.42%)d 0.04( 0.63%)
0.0000 -0.0001 -0.4117 0.0076 -0.0012
0.0000 -0.7017 0.0309 0.0000 0.4082
-0.0180 0.0000 -0.4039 -0.0260 0.0430
-0.0536 0.0312 -0.0244 0.0051

From these data it is obvious that for both NMe₄⁺ and PMe₄⁺, that both the central atom and the methyl carbons bond with an sp3 hybridised orbital (from the 25% s-character and 75% p character data). For PMe₄⁺, the central atom makes a greater contribution to the C-X bond than for NMe₄⁺ (60%, compared with 34%). This can again be explained by the fact that nitrogen is more electronegative than phosphorus, it will therefore hold on to its electrons more tightly and contribute less to the C-X bond.

SMe₃⁺ does not show such a clear structure of sp3 hybridised orbitals; the percentages are skewed. It is an intermediate case where contributions from sulphur and carbon to the C-X bond are approximately equal. Again this can be rationalised due to the similar pauling electronegativities of the two elements (both about 2.5).

Influence of Functional Groups

[N(CH3)3(CH2OH)]⁺ and [N(CH3)3(CH2CN)]⁺ were analysed in a similar way to the first three cations.

[N(CH3)3(CH2OH)]⁺

Optimisation

Log file:Media:JH_ALCOHOLFUNCTIONALISED_OPT_631GDP_ULTRAFINE_SCFCONVER9.LOG‎

Results Summary:

Item Table:

 Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000007 0.000300 YES
Maximum Displacement 0.000669 0.001800 YES
RMS Displacement 0.000154 0.001200 YES
Predicted change in Energy=-1.803887D-08
Optimization completed.
-- Stationary point found.

Frequency

Log file: Media:JH_ALCOHOLFUNCTIONALISED_FREQ_631GDP_ULTRAFINE_SCFCONVER9.LOG‎

Results Summary:

Item Table:

Item Value Threshold Converged?
Maximum Force 0.000070 0.000450 YES
RMS Force 0.000017 0.000300 YES
Maximum Displacement 0.000673 0.001800 YES
RMS Displacement 0.000221 0.001200 YES
Predicted change in Energy=-2.483545D-08
Optimization completed.
-- Stationary point found.

Low frequencies:

Low frequencies --- -8.8904 -4.6962 -0.0012 0.0005 0.0006 2.4469
Low frequencies --- 131.0428 213.4557 255.6207

[N(CH3)3(CH2CN)]+

Optimisation

Log file: Media:JAKEHOOTON_NITRILEFUNCTIONALISED_OPT_631GDP_ULTRAFINE_SCFCONVER9.LOG‎

Results Summary:

Item Table:

 Item Value Threshold Converged?
Maximum Force 0.000006 0.000450 YES
RMS Force 0.000002 0.000300 YES
Maximum Displacement 0.000326 0.001800 YES
RMS Displacement 0.000077 0.001200 YES
Predicted change in Energy=-1.464949D-09
Optimization completed.
-- Stationary point found.

Frequency

Log file: Media:JAKEHOOTON_NITRILEFUNCTIONALISED_FREQ_631GDP_ULTRAFINE_SCFCONVER9.LOG‎

Results Summary:

Item Table:

Item Value Threshold Converged?
Maximum Force 0.000011 0.000450 YES
RMS Force 0.000003 0.000300 YES
Maximum Displacement 0.000309 0.001800 YES
RMS Displacement 0.000092 0.001200 YES
Predicted change in Energy=-1.270724D-09
Optimization completed.
-- Stationary point found.

Low Frequencies:

Low frequencies --- -2.2604 -0.0006 -0.0003 0.0004 7.1270 9.6736
Low frequencies --- 91.7834 154.0362 210.9247