\documentclass[10pt]{article}

\usepackage{fullpage}
\usepackage{setspace}
\usepackage{parskip}
\usepackage{titlesec}
\usepackage[section]{placeins}
\usepackage{xcolor}
\usepackage{breakcites}
\usepackage{lineno}
\usepackage{hyphenat}





\PassOptionsToPackage{hyphens}{url}
\usepackage[colorlinks = true,
            linkcolor = blue,
            urlcolor  = blue,
            citecolor = blue,
            anchorcolor = blue]{hyperref}
\usepackage{etoolbox}
\makeatletter
\patchcmd\@combinedblfloats{\box\@outputbox}{\unvbox\@outputbox}{}{%
  \errmessage{\noexpand\@combinedblfloats could not be patched}%
}%
\makeatother


\usepackage{natbib}




\renewenvironment{abstract}
  {{\bfseries\noindent{\abstractname}\par\nobreak}\footnotesize}
  {\bigskip}

\titlespacing{\section}{0pt}{*3}{*1}
\titlespacing{\subsection}{0pt}{*2}{*0.5}
\titlespacing{\subsubsection}{0pt}{*1.5}{0pt}


\usepackage{authblk}


\usepackage{graphicx}
\usepackage[space]{grffile}
\usepackage{latexsym}
\usepackage{textcomp}
\usepackage{longtable}
\usepackage{tabulary}
\usepackage{booktabs,array,multirow}
\usepackage{amsfonts,amsmath,amssymb}
\providecommand\citet{\cite}
\providecommand\citep{\cite}
\providecommand\citealt{\cite}
% You can conditionalize code for latexml or normal latex using this.
\newif\iflatexml\latexmlfalse
\providecommand{\tightlist}{\setlength{\itemsep}{0pt}\setlength{\parskip}{0pt}}%

\AtBeginDocument{\DeclareGraphicsExtensions{.pdf,.PDF,.eps,.EPS,.png,.PNG,.tif,.TIF,.jpg,.JPG,.jpeg,.JPEG}}

\usepackage[utf8]{inputenc}
\usepackage[english]{babel}



\usepackage{float}








\begin{document}

\title{Interview with Professor Guoqing Zhang}



\author[1]{Ben Zhong Tang}%
\affil[1]{Affiliation not available}%


\vspace{-1em}



  
  \date{May 26, 2024}


\begingroup
\let\center\flushleft
\let\endcenter\endflushleft
\maketitle
\endgroup








\sloppy


Interview with Professor Guoqing Zhang

\emph{On the grand expanse, things are calm and still. But on the
microscale, waves rise and thrill. -- Zhang's own interpretation of the
physical world.}\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/image1/image1}

\end{center}
\end{figure}

Guoqing Zhang serves at the University of Science and Technology of
China as a full professor and a Ph.D. advisor. He earned his bachelor's
degree from the Department of Polymer Science and Engineering between
2001 and 2005 at the same institution. Subsequently, he pursued his
Ph.D. at the University of Virginia's Chemistry Department in the USA
from 2005 to 2010. He did his postdoctoral research at the Department of
Chemistry and Chemical Biology at Harvard University during 2010-2011.
In 2011, Zhang returned to the University of Science and Technology of
China, where he began his independent research group. He is affiliated
with the Hefei National Research Center for Physical Sciences at the
Microscale. He is primarily interested in the optoelectronic properties
of pure organic molecular materials. A notable focus of his work is on
the spin-state modulation of electrons of organic molecules,
particularly in their excited and ground states. Apart from his
research, Zhang has taught General Chemistry to undergraduate students
(\emph{http://www.hfnl.ustc.edu.cn/detail?id=11295}).

\textbf{Tang:} \emph{May you introduce your research interest and its
future development?}

\textbf{Zhang:} Since becoming an independent principal investigator in
2011, our research group has been deeply invested in exploring and
gaining mechanistic insights into organic molecular charge-transfer
systems, with a special focus on charge-transfer-mediated
room-temperature phosphorescence (RTP). The investigation of molecular
RTP serves multiple purposes. Firstly, it stands as a vital
spectroscopic method for examining electron spin in excited states.
Secondly, there is a practical imperative to innovate metal-free RTP
molecules, paving the way for the creation of energy-efficient organic
light-emitting diodes. Moreover, the potential of long-lived excited
states, such as charge-transfer or triplet states, beckons further
exploration, as they hold promise for the development of novel organic
photocatalysts and synthetic methodologies.

\textbf{Tang:} \emph{What is your understanding on aggregate science?}

\textbf{Zhang:} The future trend in fundamental research will likely
focus on characterizing physical matter that is shorter in time, more
microscopic in space, and more intricate in scale, using sophisticated
instrumentation. That said, the field of aggregate science is no
exception. This holds even truer for organic aggregates, whose
interactions display profound disorder and complexity, both
energetically and spatiotemporally. The \emph{status quo} of research on
organic aggregates centers largely around chemical synthesis and
relatively simple characterization. This trend has persisted for over
twenty years since Prof. Ben Zhong Tang first introduced the concept of
''aggregation-induced emission'', or AIE. While chemical synthesis is
undoubtedly the foundational pillar for studying aggregate science, we
are only beginning to scratch the surface of this domain.

We've made significant progress in synthesis, and the new frontier in
aggregate science is now moving towards quests for precision
measurement, theoretical modeling, and understanding the novel
properties of microscopic particles \emph{en masse} . No single particle
exists in complete isolation. In essence, there is only one single
quantum mechanical equation encompassing all possible interactions that
can describe the entire universe. In the early days of ``cowboy
science,'' we often overlooked what we deemed to be negligible
interactions, basing our conclusions on experiments with these
purportedly isolated systems. However, we are now beginning to recognize
that even the weakest couplings must be considered, as they might hold
the key to overcoming significant scientific challenges.

A prominent example of this is the microscopic origin of gravity, which
seems incompatible with the laws of gravity observed on a planetary
scale. While galaxies are just aggregates of massive numbers of
microscopic particles like neutrons, atoms, and molecules, the same
gravitational effects don't appear to manifest among these smaller
entities. This inconsistency has become one of the most significant
unsolved mysteries in contemporary physics. This aligns with what Prof.
Ben Zhong Tang has often emphasized in his lectures: reductionism may
not be the best approach for addressing issues in aggregate science.
This might be why, in my opinion, physicists find themselves at an
impasse.

There are numerous examples in chemistry that mirror this conundrum,
such as the physical description of weak intermolecular interactions. A
particular case in point is the nature of hydrogen bonding. Whether it's
more rooted in covalent/charge-transfer or electrostatic interactions
has been a subject of debate for over a century, with no definitive
resolution in sight. Yet, we have a comprehensive understanding of the
chemistry and physics of a drop of water. The missing piece clearly
resides in aggregate science -- how do water molecules, as quantum
objects, aggregate to produce the microscopic properties of a droplet? I
believe merely attributing this to the ``uncertainty principle'' or a
``phase transition'' is vague and insufficient. Modern chemistry demands
more details, like how a gigantic group of water molecules coordinate
their electrons and nuclei during the transition to give rise to
emergent properties explainable mathematically. Otherwise, we risk
remaining at a standstill.

Speaking of being stuck, I believe no field demands a grasp of aggregate
science more than the life sciences. Life itself is a special form of
molecular aggregates. Yet, despite possessing state-of-the-art
equipment, biologists have not fully connected the dots between a wad of
molecules and a rudimentary living organism, such as a bacterium. The
ultimate quest in life science might be to comprehend why we are
conscious entities, a question that, to this day, remains elusive.
However, I dare to make a guess that a prerequisite for consciousness is
memory, which runs on some type of ``molecular hard drive.'' The act of
forming memories might involve changes in the aggregation state of these
drive-constructing molecules, akin to optical or magnetic hard drives.
To tackle such a challenging ``aggregation'' issue, collaborations
between physicists, chemists, biologists, and engineers will be
indispensable.

The examples I've mentioned concerning molecular aggregates pertain
largely to systems in the ground state. However, when these systems
transition to the excited state, the complexity becomes almost
unfathomable. This is because the number of potential microscopic
states---and consequently, the modes of interactions---multiply
exponentially. In reality, unless measured at temperatures near absolute
zero, all systems under experimental conditions are in excited states.
But in the context of aggregate science, such as with AIEgens, ``excited
systems'' typically refer to electronic excited states. These states can
display lifetimes that vary widely, ranging from femtoseconds to
seconds---a staggering 15 orders of magnitude. Grasping this
spatiotemporal intricacy demands modern chemists not only to master the
art of molecule creation but also to embrace a comprehensive, holistic
view offered by aggregate science.

In summary, in chemical science, we are fully capable of addressing
issues concerning individual molecules or even a small group of them.
The advent of supercomputers has empowered us to calculate the
properties of thousands of atoms with remarkable precision. The real
challenge emerges when trying to comprehend how myriad weak interactions
among these microscopic entities, spanning diverse timescales, culminate
in the macroscopic behaviors we observe. This presents a daunting task,
primarily because our prevailing theory for the minuscule, quantum
mechanics, demands a composite of numerous possible patterns. Revisiting
the gravity example, how can space itself oscillate among different
configurations? And if it does, in which version of space do we exist?
It's pretty evident to me that a reductionist approach will only take us
so far.

Aggregate science, on the other hand, circumvents our old routine of
quantizing whatever macroscopic things we encounter, a typical
reductionist approach. Instead, it redirects our attention to
potentially solvable problems when considered from a slightly elevated
perspective. For instance, a semi-classical approach that factors in
quantum mechanics and varying aggregation statistics when studying
colloidal particles could provide insights into some paradoxes within
the field. With this in mind, I genuinely hope that more people will
gravitate towards these intriguing challenges, holding onto the optimism
that aggregate science may someday illuminate the answers.

\textbf{Tang:} \emph{Why did you choose to pursue a career in scientific
research?}

\textbf{Zhang:} I think being able to live a life is so precious that we
can't afford not to know the physical laws governing our universe;
otherwise, life seems unfulfilled. Moreover, engaging in scientific
research allows one to remain distant from worldly concerns without
hiding in a monastery, leading to a simpler life.

\textbf{Tang:} \emph{Where do you think the greatest charm of science
lies, and how did you resolve to pursue a career in scientific
research?}

\textbf{Zhang:} The true allure of science is its ability to grant us
the ability to predict the future. Why do humans experience anxiety? It
boils down to a lack of security. And why this insecurity? That is if we
don't know what's going to happen in the next moment. However,
scientific laws will tell us how things will evolve to a very good
extent, alleviating our anxieties. I decided to become a full-time
scientist when I realized the enormous freedom this career offers,
especially at USTC (University of Science and Technology of China) --
where there's autonomy to pursue what you desire. I mean I get paid for
just coming up with new ideas and testing them? How is this different
from living in heaven?!

\textbf{Tang:} \emph{Do you have any academic aspirations you'd like to
achieve? Would you mind sharing your short-term goals and long-term
vision with our readers?}

\textbf{Zhang:} My short-term objective is to secure funding from the
National Natural Science Foundation's Outstanding Youth Program. In the
long run, I aim to win a globally recognized scientific award.

\textbf{Tang:} \emph{What has been the most memorable experience in your
research career?}

\textbf{Zhang:} When I first accidentally observed the room-temperature
phosphorescence of the polymer I synthesized, I excitedly showed it to
my Ph.D. advisor, Professor Cassandra Fraser. Her response was, ''What
the heck is that?''

\textbf{Tang:} \emph{Could you describe some exhilarating moments in
your research career?}

\textbf{Zhang:} On one occasion, we identified a method for specifically
marking solid tumors for surgeries using luminescent molecules. Dr. Xu
from Professor Guoqiang's Bi research group exclaimed, ''Professor
Zhang, does this mean we'll soon afford a Boeing 777?''

\textbf{Tang:} \emph{Have you encountered any bottlenecks in your
research career? How did you overcome these challenges and maintain your
determination?}

\textbf{Zhang:} For a time, I struggled to find a breakthrough in
organic room-temperature phosphorescence. But now, as I delve deeper,
the path becomes increasingly clear, akin to discovering a hidden utopia
as described in the classical Chinese masterpiece ``The Peach Blossom
Spring''.

\textbf{Tang:} \emph{Where does the pressure in your job come from, and
how do you manage it?}

\textbf{Zhang:} I've never felt pressured in my job, a sentiment that
all my colleagues and students can attest to.

\textbf{Tang:} \emph{What qualities do you hope students in your
research group possess? Do you have any messages for your current and
future students?}

\textbf{Zhang:} I hope they have a solid foundation in mathematics and
physics and are adept at hands-on tasks; with these skills, they would
be unbeatable. During challenging times in the lab, I hope they never
doubt themselves, and believe that among the myriad of complex chemical
systems, there's certainly one tailored for them.

\textbf{Tang:} \emph{What do you believe is the most important quality
for a scientific researcher?}

\textbf{Zhang:} Curiosity and perseverance are paramount, and you need
both to succeed.

\textbf{Tang:} \emph{If you could go back to your graduate years, is
there a new career you would like to pursue?}

\textbf{Zhang:} If I had prior knowledge of the developments of China
over the past two decades, I might have pursued a career in foreign
trade. This way, I could have traveled around the globe much earlier.

\textbf{Tang:} \emph{What hobbies do you have outside of your scientific
work?}

\textbf{Zhang:} I enjoy watching movies and writing novels, and I'm
currently obsessed with The Legend of Zelda: Tears of the Kingdom.

\textbf{Tang:} \emph{As the Next Generation Board Member of Aggregate,
What are your expectations and suggestions for the development of the
journal?}

\textbf{Zhang:} The starting point of \emph{Aggregate} is very high, and
everyone has high hopes, believing it's worth the lifetime investment! I
hope that in the future, it adheres to the highest standards, treating
each manuscript impartially. It's vital to not show favoritism, even
towards the journal's routine authors, including members of the
editorial board like us.

\emph{Zhang's comment on his Aggregate paper entitled ``Kinetic and
thermodynamic control of tetraphenylethene aggregation-induced emission
behaviors''\textsuperscript{{[}1{]}}:}

Tetraphenylethene (TPE) is a classic example of an Aggregation-Induced
Emission (AIE) system. In good solvents, it doesn't display any
photoluminescence. However, in poor solvents, it exhibits sky-blue
fluorescence emission. During the experiment, we noticed subtle changes
in TPE's AIE emission wavelength and peak maximum and spectral shape
over time. By synthesizing various derivatives, we discerned this
phenomenon is prevalent during AIE sample preparation. Organic
molecules, when aggregating rapidly, might be locked into a kinetically
metastable state that remains stable at room temperature. But this
kinetic stability can transition to a thermodynamically stable
aggregated state when heated or when exposed to good solvents. Depending
on the molecular structure, these kinetically aggregated species and
thermodynamically aggregated species display vastly different
luminescent phenomena. This topic underscores that the physical
properties of organic aggregates are highly sensitive to their
surroundings and offers crucial theoretical insights for precision
synthesis of an AIE system.

REFERENCES

X. Nie, W. Huang, D. Zhou, T. Wang, X. Wang, B. Chen, X. Zhang, G.
Zhang, \emph{Aggregate} \textbf{2022} , \emph{3} , e165.
https://doi.org/10.1002/agt2.165

CONFLICT OF INTEREST

The author declares that there is no conflict of interest.

\selectlanguage{english}
\FloatBarrier
\end{document}

