*(Fig.1) Classical molecular mechanics can handle large molecules ?*

Nobel prize was given to computational chemistry such as molecular mechanics ( or dynamics ) in 2013. Can we apply this new method in actual daily lives ?

Unfortunately, this Nobel-prize method is **useless**, forever.

This method can be used **neither** as ab-initio nor as chemical reaction ( this p.2 )

*(Fig.2) This methods just fit the model to experiments, NOT predicting.*

This new computational method, molecular mechanics uses some "**classical** approach" to calculate large molecules, which quantum mechanics cannot handle.

In fact, this molecular mechanics **cannot** predict any new *physical* values, because its model must rely on **existing** experimental values (= empirical ).

So this model's parameters must be adjusted in advance to **fit** experimental data. Molecular mochanics cannot be used to predict new chemical reactions.

*(Fig.3) This classical method doesn't consider electrons. ← impractical.*

This molecualr mechanics treats each atomic bond as classical spring or something. Of course, real atomic bonds are **different** from classical spring !

Surpridingly, this method ignores the existence of electrons !
Instead, it adjusts the classical spring constant (= **fake** ! ) depending on experimental data.

This method uses "virtual" classical potential (= force field, this p.9 ) where its potental energy is lower as the bond's length, angle are closer to "adjusted points".

*(Fig.4) Parameters (= bond length, angle, torsion ) are adjusted artificially.*

This molecular mechanis treats actual atomic bonds as "*virtual*" (= **fake** ) classical spring, **ignoring** electrons. Without considering electrons, how is it useful ?

All *parameters* (= bond length, angle, torsion .. ) used in molecular mechanics must be adjusted in advance to fit existing experimental data ( this p.9 ).

So this molecular mechanics needs a large number (= 10^{6} ! ) of different parameters depending on **different** combinations of atomic bonds ( this p.5 ).

*(Fig.5) Because its parameters depend on "existing" experimental data.*

Molecular mechanics depends on "existing" experimental data, and **ignoring** actual electrons, so we cannot use this method to predict new chemical reactions.

Balanced bond length and angle used in potential fields are **fixed** in advance, so new bond breaking is **impossible** in molecular mechanics.

As a result, this computational method is **useless** forever despite getting Nobel prize.

*(Fig.6) QM/MM (= quantum mechanics / molecular mechanics )*

Quantum mechanics cannot handle large molecules, and molecular mechanics cannot be used for chemical reaction, so physicists try to combine them.

This new method is called "QM/MM" (= quantum mechanics / molecular mechanics ). Density functional theory (= DFT ) is often used in this p.4

But even this combined QM/MM remains **useless**, too, despite the media-hype.

Because quantum mechanical methods **cannot** solve muti-electron atoms, it just **chooses** artificial trial functions, so meaningless.

*(Fig.7) No solution → just "choose" trial functions ! = useless*

Schrodinger equation of two-electron helium contains interelectronic Coulomb energy. So it has No solution of helium.

All other multi-electron atoms including H2+ molecule ion have **No** exact solution. Then how does quantum mechanics deal with multi-electron atoms ?

Surprisingly, they just choose **artifical** trial function as "*imaginary*" solution.

"Choosing" convenient hypothetical solution out of **infinite** choices means Schrödinger equation has **no** ability to predict multi-electron atoms.

And it's **impossible** to try *infinite* kinds of trial wavefunctions and find the one giving the lowest energy in them.

*(Fig.8) ↓ Variational method of Helium is impractical.*

In the present **useless** quantum mechanics, they just guess and **choose** some trial function and adjust their free parameters to obtain desired energies in helium.

The problem is there are "**infinite** free choices" in this trial wavefunctions, so we **cannot** try all possibe wavefunctions to compare their energies.

It means finding the lowest ground state energy by trying infinite choices is **impossible** in quantum wavefunction !

All these trial function don't satisfy the total energy conservation, so "fake" energy, after all, meaningless.

The present use of "**finite**" basis set as approximate function **never** represents truth ( this p.4 )

*(Fig.9) Electron interaction term is freely chosen. ← useless*

In larger atoms in condended matter physics, density functional theory (= DFT ) is the **only** computing method.

It is often said this DFT is successful "ab-initio" method ( this p.3 ).

"Ab-initio" means first-principle which can predict values without empirical parameter ?

Unfortunately this DFT has **No** ability to predict any values, so **useless**.

Like this, DFT just **chooses** some convenient functional out of *infinie* choices.

In DFT, "exchange correlation functional" means interelectronic repulsions. This functional is **unknown**, can be *freely* determined ( this p.2 ).

So DFT can be considered a semi-**empirical** method, *different* from media-hype ( this p.23 ), and our basic science stops !

*(Fig.10) Unknown exchange-correlation energy can be freely determined !*

Density functional theory (= DFT ) does **NOT** have the standard "form" of interelectronic Coulomb energy and Pauli principle from the beginning.

So in DFT, physicists have to choose and determine "convenient form" of interelectronic repulsions out of **infinite** choices !

Artificially **choosing** convenient forms means DFT has **NO** ability to predict any physical values like ordinary Schrodinger equation !

So DFT is one of empirical methods, NOT first-principle at all.

*(Fig.11) Fatal cancer, HIV, ALS, dementia remain incurable.*

If **basic** quantum mechanics remains **useless** and unrealistic, all other applied fields such as
solid-physics and biology remain useless, too.

This is a serious problem, because it's impossible to cure fatal diseases such as cancer, HIV, ALS.. forever, as long as we believe **fictional** physics !

*(Fig.12) Molecular mechanics with NO electrons is impractical, despite Nobel*

New computational approach, molecualr mechanics was awarded Nobel prize in 2013. But this method contains **NO** real electrons !

All parameters in virtual classical model are artificially **chosen** in advance, so **NO** new chemical reactions can be predicted.

I'm afraid prestigious Nobel prize is exploited as a convenienet tool only to *advertize* greedy for-profit universities and fraudulent journals.

This tendency is very **dangerous** and harmful to science and young students !

2016/6/17 updated. Feel free to link to this site.