Chapter 1574 Sugar-coated bullets
That evening.
Beijing, Xijiao Airport.
Chang Haonan had just sat in the back seat of the special car when the phone in his pocket vibrated.
It’s a text message from Li Yabo.
[Teacher, the exchange-correlation functional calculation phase has been completed. But in some cases, it is best to report in person. ]
The Torch Laboratory requires that communications equipment be domestically produced as much as possible, but it is still impossible to say any details on the phone.
Chang Haonan hesitated for a moment and said to the driver in front:
"Xiao Qin, go to the Torch Laboratory."
When Chang Haonan changed his clothes and walked into the computing center, Li Yabo was already waiting next to the main operating table.
Seeing the former come in, he immediately greeted him: "Teacher, you are here."
"Yeah." Chang Haonan buttoned the top button of his work clothes and signaled the other party to report the situation.
Li Yabo pointed to a row of densely packed documents on the screen:
"This is the computational model of the nickel-cobalt diatomic array on the multi-level channel hollow carbon nanoparticle substrate obtained at this stage, including electron cloud distribution, bonding energy, possible catalytic pathways, etc."
Chang Haonan sat in front of the screen, dragged the mouse, and carefully examined the configuration of the lowest energy point and the charge density distribution of the active site.
The parameters involved in the chemical model were extremely complex, and even he couldn't check them all in a short time.
So I asked while rolling the mouse wheel: "What did you mean by 'some situations'?"
Li Yabo turned around and walked to the side, picking up a stack of bound paper reports:
"Teacher, please take a look at this."
Chang Haonan took the report and quickly glanced at the cover.
The logo of Lianhai Institute of Chemical Physics is printed in the middle.
"Laboratory report?" His tone was somewhat surprised. "I remember that the synthesis test has not been officially arranged yet."
"Academician Zhang Tao is very enthusiastic," Li Yabo explained. "They have already started trying to synthesize the 'nickel-cobalt diatomic array multi-level pore hollow carbon nanoparticles' you designed, just to practice and accumulate experience..."
As he spoke, he picked out a few reports from a pile and laid them out in front of Chang Haonan:
"Some of them looked good, so I took them and did a few basic pre-screenings, but...some of them didn't match."
While listening, Chang Haonan casually flipped through the report.
"It's good to practice and get familiar with the process." His tone is quite relaxed. "It's normal that the data doesn't match the model. After all, the calculation is based on ideal conditions and there are deviations in the synthesis. The test conditions also vary greatly... Our model is to guide the direction, not to pursue the consistency of every result data."
"It's not just the specific values that don't match," Li Yabo shook his head. "The key is... the regularity between samples from different batches is different from the trend predicted by our model."
Chang Haonan slowed down his mouse operation.
Li Yabo added, "This has never happened before when we were studying one-dimensional arrays..."
Chang Haonan finally took over the report: "Are you sure that the correct array structure has been formed?"
The first thing that came to his mind was naturally the problem of synthesis technology.
"The pieced-together device can only observe the existence of a super-one-dimensional arrangement, and cannot accurately anchor the specific position of a single atom," Li Yabo explained. "But according to current computational theory, even if the actual array structure of the product is different from the design, it should not show completely different new characteristics."
"A new feature?"
Upon hearing this, Chang Haonan flipped to the end of the reports, his eyes moving quickly between the data analysis and conclusions.
Soon, the relaxed look on his face faded and his brows furrowed slightly.
"interesting……"
He compared them back and forth several times, then divided the reports in front of him into three piles.
"Apart from the differences in simple numerical values, these test results can be roughly divided into three categories."
Chang Haonan pointed at the three copies on the far left:
"These are consistent with our expectations. The efficiency of adsorption and conversion of polysulfides is very high, the cycle expansion rate is low, and the effects of inhibiting shuttle and buffering volume expansion are also good."
Then, he pointed to the four in the middle and said, "This type of catalytic selectivity has problems. The catalytic activity for harmful side reactions seems to be higher than that of normal battery reactions... The capacity decay will definitely be accelerated, and even thermal stability may have problems."
Li Yabo nodded, regretting that he had not thought of classifying them in advance.
"And the last two." Chang Haonan's expression was even more confused. "The catalytic activity is similar to the first type, but the particles will easily turn into powder and fall off on the electrode sheet..."
He even re-confirmed the data in the report:
"The substrate was hardly touched during the entire synthesis process, so how could the physical stability be so poor?"
Differences in array structure theoretically mainly affect chemical activity and selectivity.
The physical and mechanical properties, such as the adhesion strength of the particles on the electrode and their resistance to pulverization, mainly depend on the characteristics of the base material itself, and should have little to do with the loaded nickel and cobalt atoms themselves, including their arrangement.
Obviously, Li Yabo did discover an abnormal situation.
However, in the absence of effective means of observation, it seems that we can only guess where the abnormality is.
Chang Haonan fell silent and turned his gaze back to the big screen that was still running the calculation results.
Li Yabo was getting a little impatient waiting nearby, but he didn't dare to disturb his mentor's thoughts.
Of course, in reality, Chang Haonan was not really thinking.
But it was a little bit of a cheat.
However, the problem at hand is indeed complicated, and even if it is a hang, it will take some time to give a result.
Time passed by minute by minute.
"Yabo," after a long wait, Chang Haonan suddenly spoke up, breaking the silence again, "I have an idea."
Of course he couldn't say that he had already figured out the result, so he could only ask the other party to verify it in the name of speculation.
"You say."
Li Yabo came closer,
"Since there was no problem with the previous calculation of the one-dimensional array, it means that the starting point of the entire model is correct." Chang Haonan said, "So, it is likely that a certain variable was ignored in the process of extending a certain theory or algorithm to a high-dimensional array..."
He opened his notebook, took a pen directly from Li Yabo's work clothes pocket, and wrote on it while explaining:
"Considering the characteristics of our system, new variables will appear in the process of dimensionality increase. The most likely one is the radius of curvature of the carrier surface..."
Li Yabo took a closer look and said thoughtfully: "You mean that the high curvature of the substrate will significantly change the local environment of the loaded atoms?"
"Hmm..." Chang Haonan tried to sound less certain. "The high-curvature surface will strongly distort the local electronic structure, causing the charge distribution to no longer be uniform and highly localized hot spots to appear. More importantly, it will introduce a strong strain effect at the atomic scale."
He drew a schematic diagram of the structure in his notebook: "In turn, when two highly active atoms are loaded on such a highly curved surface in a specific configuration, the interaction between them and the bonding between them and the substrate will further cause a significant modulation of the strain field..."
"..."
After all the theories were explained, it was not known whether Li Yabo understood them or not, but Chang Haonan's own thoughts became much clearer.
Finally, he tore off the two pages he had just written and put them in Li Yabo's hands:
"That's right, we can conduct research in this direction next!"
Li Yabo finally came back to his senses, lowered his head and quickly browsed the diagrams and formulas above, his eyes full of excitement.
But soon a trace of worry appeared:
"If we want to include the variable of substrate curvature, as well as the strain field and charge redistribution effect it induces as key independent variables in the model, and consider their dynamic coupling with the array configuration... this amount of calculations will be very large..."
"I'm afraid it will be more than an order of magnitude higher than it is now." Chang Haonan calmly replied, "The variable dimensions will surge, requiring more complex multi-scale simulation methods, and the computing resources and time will increase exponentially."
Li Yabo's expression suddenly fell a little: "Then... this..."
"Don't worry." Chang Haonan patted his shoulder. "Anyway, it's still a long way to go before the commercialization of TEM-APT combined equipment is available. It will take at least a year to get it ready. We have enough time to revise the model... We can even try a few more directions. After all, in scientific research, who knows what will be useful..."
……
Almost at the same time.
Lianhai Institute of Chemical Physics.
Wang Lingxiao trotted into Academician Zhang Tao's office with a laptop in his arms, without even knocking on the door.
"Teacher Zhang! Teacher Zhang!" He was slightly out of breath, with a look of surprise and uneasiness on his face.
Zhang Tao, who was reviewing a project book at his desk, saw Wang Lingxiao's expression and thought something had happened in the lab. His heart tightened:
"What's wrong, Ling Xiao? Which group's response went wrong? Or the equipment?"
"It's not an experiment." Wang Lingxiao shook his head. "I received an email..."
He placed his laptop on the desk and pointed to the top of the screen:
"Look at this!"
Zhang Tao put on his reading glasses puzzledly, leaned closer to the screen, and clicked on the email details.
The sender's address suffix is clearly visible: @ias.edu - Princeton Institute for Advanced Study.
The content is elegantly worded and full of academic flavor.
First, he praised Wang Lingxiao for his outstanding work and said that he "has demonstrated extraordinary insight and potential."
Then, he enthusiastically introduced the academic tradition and top research environment of IAS.
Finally, we asked Dr. Wang Lingxiao whether he was interested in joining IAS after graduation to explore the frontiers of science with the world's top scholars, and promised to provide highly competitive remuneration and completely free research support.
After reading it, Zhang Tao smiled with relief:
"That Nature paper really had an immediate impact. It was only published a few months ago, but it has already been picked up by others."
He changed his tone to a half-joking one: "Okay, keep the email. It will allow IAS to recruit you actively. It will also be a good thing to tell others about it later."
The Institute for Advanced Study in Princeton, where both Einstein and von Neumann worked.
Deserves such an evaluation.
And Zhang Tao was not worried at all that his students would be poached.
However, there was no joy on Wang Lingxiao's face, but rather he looked more solemn.
He shook his head and said in a low voice: "Teacher Zhang, I just asked several other people in our research group privately, including Senior Brother Li and Senior Sister Zhao... As a result, several people said that they had received similar emails recently..."
"You received them all?" Zhang Tao's smile froze instantly. "The contents are the same?"
"Not exactly the same," Wang Lingxiao said quickly, "The one sent to me was from IAS. Senior Brother Li received an invitation letter from a chair professor in the Department of Materials Science at MIT, and Senior Sister Zhao received one from the Royal Society of Canada. And Xiao Liu is from Dow Chemical, and the salary is very high..."
