Ethylene carbonate, also known as ethylene carbonate, 1,3-dioxanecyclo-2-one, 1,3-dioxanepentanone carbonate .....

Its chemical formula is 'C3H4O3', it is a crystalline solid at room temperature, but when the temperature is greater than 35C, it becomes a transparent and colorless liquid. It is an organic solvent with excellent performance, which can dissolve a variety of polymers. It is used in fertilizer, fiber, pharmaceutical and organic synthesis industries.

As a materials researcher, Xu Chuan has some understanding of ethylene carbonate compounds, but not much.

After all, his materials research in his previous life was mainly focused on physical materials, while ethylene carbonate belongs to the category of chemical materials.

However, it is not difficult for him to understand the properties of a material and find another additive that can control it.

Everything is mutually reinforcing, and so are materials.

Different materials have different chemical and physical properties, and the blending between molecules is to find order in disorder, simplicity and beauty in complexity, or destruction or rebirth.

For example, the amorphous alloy material looks extremely hard, but it is not absolutely orderly, and in the never-ending flow, like Van Gogh's "Starry Night", if you look closely, it is perpetual in seemingly motionless.

This is the beauty of materials science.

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"Ethylene carbonate: the molecular formula is C3H4O3, the molar refractive index in the molecular structure is 17.17, the surface tension is 37.3, the dipole distance is 10-2?cm3, and the polarizability is 6.80....."

"Number of hydrogen bond donors: 0, Number of hydrogen bond acceptors: 3, Number of rotatable chemical bonds: 0, Number of tautomers: none, Topological molecular polar surface area 35.5, Number of covalent bond units: 1......"

"It can be miscible with hot water, alcohol, benzene, chlorographic, ethyl acetate, acetic acid and other items above 40C. Insolu......ble in dry ether, carbon disulfide, carbon tetrachloride, petroleum ether, etc.

In the laboratory, Xu Chuan listed all the information about ethylene carbonate little by little.

Whether it is its chemical and physical properties, or various previous studies.

These things are of great help in finding materials to control ethylene carbonate.

In fact, to find a material to control ethylene carbonate, he could have gone to other chemical researchers for help.

For those chemical researchers who have been immersed in this for many years, it is not too difficult to find a few materials that meet the requirements.

However, Xu Chuan has other ideas, he wants to try it and see if mathematics can be integrated into materials science calculations.

Just as others speculate that he relied on strong mathematical skills to develop anti-nuclear radiation materials and lithium battery materials.

Only he knew it wasn't.

And today, Xu Chuan wants to take this step and use mathematics to help him complete this work.

For chemical reactions, in textbooks it is the transformation of lines and lines of chemical formulas, in the laboratory, it is the breaking of old chemical bonds and the formation of new chemical bonds.

For example, the essence of redox reactions is the gain and loss of electrons outside the nucleus, and the structure of the atom itself changes.

The essence of metathesis reaction is atomic rearrangement, that is, the arrangement and combination of multiple atoms change.

But in reality, its deeper essence is the flow of electron clouds.

To determine whether a chemical reaction can occur, it is necessary to confirm from thermodynamics, kinetics, enthalpy, entropy, free energy (gibbs free energy), activation energy and other aspects.

In fact, strictly speaking, the current development of chemistry is not perfect.

Because we often can't explain even the simplest chemical reactions in theory, many theories are phenomenistic.

If we follow the chain of explanation of chemistry, it will eventually come down to the explanation of physics.

Therefore, physics is the most basic subject in the natural sciences (mathematics is not a natural subject!). ）。

Many people mistakenly think that chemistry is the most basic, because chemical bonds are essentially an electrical interaction, which belongs to the electromagnetic interaction among the four fundamental forces. The progress of chemical reactions is also related to the movement and collision of molecules.

Of course, chemistry has a lot of potential and great value to dig deeper.

And if we look at the deeper nature of chemistry, there is no doubt that mathematics can be applied.

For example, the rate of the most common chemical reaction can be described by calculus equations. Mathematical equations can be solved using numerical methods to determine the reaction rate constant and other parameters.

For example, wave function theory, group theory, etc., are used to describe the electronic structure and reaction mechanism.

Or molecular dynamics simulation, which uses a kind of computer mathematics to study the laws of motion of matter. It involves a lot of knowledge of calculus, probability statistics, and optimization algorithms.

In addition, there are thermodynamics, analytical chemistry, and other aspects of things, which can be carried out through mathematics.

Theoretically, if we know the relevant information and conditions of the materials that need to be used for chemical reactions, it is completely possible to simulate the whole process of the reaction mathematically.

It sounds incredible, but the theory works.

Of course, in reality this is an impossible thing, at least not for now.

And what Xu Chuan wants to do is to try to take the first step towards this impossible thing.

Ethylene carbonate is a good target.

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"Considering the polymer solvents and cathode and anode materials used in the electrolyte, the range of additives to control ethylene carbonate is not very large."

"Most of the alkaline compounds and alcohol compounds can basically be eliminated, and these compounds will react with ethylene carbonate to form various substances harmful to the battery, not to mention the corrosion of the positive and negative electrodes, and they cannot be cycled."

"Then there are not many options left, and some materials such as ketones, fluorides, and rings can be considered."

"Screening based on reversibility conditions, ketones linked to two hydrocarbon groups with carbonyl groups are a good choice."

"But the range of ketones is still too big, so we have to shrink a bit......"

In the laboratory, Xu Chuan muttered to himself non-stop, and the ballpoint pen in his hand was constantly recording the data of one item on the A4 manuscript paper.

He is doing a rough screening of the available additives based on some basic chemical reactions, and then using mathematics to simulate and select the reactions.

This is a very challenging road, although it is not untouched, but it is not deep; The path with no end in sight, thorny in the unknown fog, requires a person to muster up the courage to move forward.

Fortunately, he has never lacked the courage to explore and face difficulties.

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In the laboratory, Xu Chuan is constantly improving his theories and data.

On the other hand, testing of new artificial SEI films and ethylene carbonate content is also ongoing.

Five or six days passed in the blink of an eye.

When Xu Chuan was still looking for suitable materials, the tests on the side of the Chuanhai Materials Laboratory had basically been completed.

"Director Fan, this is the experimental and test data of these days, from the experiments of these days, if other materials and additives are not changed, the content of ethylene carbonate is reduced to about 67.3% of the original base is the most suitable number."

In the laboratory, Yu Zhen, a formal researcher who was originally in charge of artificial SEI thin film research, handed over a thick plate of report materials.

Fan Pengyue nodded and stretched out his hand to take it: "Thank you for your hard work." ”

Yu Zhen shook his head and replied: "I'm ashamed to say that we didn't play any role in the research and development of lithium battery materials this time. ”

"From the very beginning of the theoretical and experimental process, to the later solution of the problem of artificial SEI film, as well as the discovery of the problem of ethylene carbonate interfering with lithium dendrite and lithium precipitation, all of them were handled by the boss."

"We just conducted an experiment according to his requirements, and this kind of experiment can be done by any master's student who has done lithium battery experiments."

Hearing this, Fan Pengyue also sighed.

"He is indeed perverted, at the age of twenty-one, he has won the highest glory in the world of mathematics and physics at the same time, this is no longer a person of the same world as us."

"I believe that no matter what industry he is in, he can show the most terrifying ability."

After a pause, Fan Pengyue continued: "Do you know? When I was still a Ph.D., I followed my supervisor to do a tungsten diselenide material project, and I encountered a problem that almost made my supervisor give up the project. ”

"The latter little brother not only helped solve this problem, but also used mathematics to find the root cause of the problem and find a solution."

"And that one project, the results are worth billions of dollars!"

"What's more, he was still a freshman at the time."

Hearing this, Yu Zhen gasped.

He knows who Fan Pengyue's mentor is.

After all, several months have passed, and some of the usual chats and conversations are enough for everyone to get to know each other.

It's not just their boss, but the airborne director in front of him is actually not bad. A disciple of an academician of the Academy of Sciences, this interpersonal relationship and status are not comparable to these people.

And a project that an academician almost gave up must have encountered a fatal problem.

Although I know that the Nobel Prize and Fields Medal double winners are not from the same world, when I am a freshman, I can participate in a project worth billions of meters of gold and solve deadly problems.

This talent is indescribable.

But looking back, Yu Zhen suddenly felt reasonable again.

If it weren't for such a wickedness, how could he solve a problem that academicians couldn't solve, and win the Nobel Prize and the Fields Medal at the age of twenty-one? These are two of the most prestigious awards in the academic world.

Although shocked, this mathematical ability also made Yu Zhen a little curious.

He couldn't help but ask, "You say, if you are good at mathematics, is it really that good?" Materials, a field that is difficult to apply mathematics, can also be solved by mathematics? ”

Hearing this question, Fan Pengyue was silent for a while, and after thinking about it, he replied a little confused: "I don't know." Maybe yes to him? ”

After a pause, he cautiously added, "But I have never seen this level of mathematical application in other mathematics professors. ”

"Maybe he's special."

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On the other side, in the office, Xu Chuan was prostrate in front of his desk, the ballpoint pen in his hand was constantly writing.

“....... ec，(c) dec，(d) dmc，(e) emc，(f) ec/dec = 1/1，(g) ec/dmc = 1/1，...... (j) ec = 1/2。 ”

“........”

Staring at the data on the manuscript paper, Xu Chuan fell into deep thought.

"Judging from the data, methyl ethyl ketone is a good choice, and according to the chemical properties, it can play a certain role in inhibiting ethylene carbonate."

"As we all know, the reason why ethylene carbonate plays a great role in lithium-ion batteries is that it can form a tightly ordered Li+-EC solvation configuration with Li+ through solvation, so that the EC-containing electrolyte is more stable during cycling."

"Because the 'Li+-ethylene carbonate solvent' configuration has higher stability than other solvated lithium ions, such as methyl ethyl carbonate, the addition of 'Li+-ethylene carbonate solvent' component to the electrolyte can significantly improve the cycling performance and voltage polarization of the battery."

"This not only improves the stability of the electrolyte, but also helps the reduction product of the ethylene carbonate to form a stable solid electrolyte interfacial film, making the electrolyte more stable during circulation."

"Methyl ethyl ketone can be used in it through lithium ion deposition/expulsion, thereby weakening the lithium evolution of the anode to a certain extent."

"As for the specific situation, experiments need to be carried out, after all, there must be some differences between the estimated data and the actual application."

Thinking about it, Xu Chuan shook his head again, looked at the manuscript paper on the table and breathed a long sigh of relief.

These days, he's put aside other projects and focused on working on this issue, and when it comes to progress, there's some progress, but it's not much.

So far, he has only found a material that might be suitable.

He underestimated the various collateral phenomena that can occur in chemical reactions. These things can be calculated to exhaust a person.

"Perhaps, I should come up with a mathematical model?"

In his mind, Xu Chuan turned his thoughts to the other side.

Although a mathematical model cannot accurately predict the properties of untested material samples and the chemical coincidence that may arise, it can provide a certain reference for users.

For example, narrowing down the scope of the experiment in a probabilistic sense.

A long time ago, when he was a freshman, he made a mathematical model for his mentor Chen Zhengping about the tungsten diselenide material project, and then quickly helped find the problems in the experimental process and lock in the concentration of the best reducing substance.

It can be said that in the research and development process of materials, a mathematical model still plays a great role.

It's just that he doesn't have that much time to do this now.

It should be possible to make a mathematical model for the research of chemical materials, but in terms of difficulty, it is definitely much greater than the one he used to make for his mentor Chen Zhengping.

It can even be said that it is one day and one earth.

After all, the tungsten diselenide material project is only a material, even if there are reducing agents, temperature, air pressure and other conditions, it is not very complicated.

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But chemistry is different, and this kind of mathematical model for the exploration of chemical materials is simply beyond the sky.

Even if he led a team of more than a dozen people to write it, it could take months.

Of course, if successful, it can bring great convenience to his future chemical experiments.

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