Yonghe Zhang (born 27 October 1940, another name Huilin), an American scientist.  He is the most influential proponent of  Ionocovalency (IC) theory: “Everything exists in ionocovalent potential”.

He proposed many chemical models and parameters: Effective nuclear charge, IC-Model (Full-Text),  Ionocovalent electronegativity, Lewis cation strengths, Ionocovalent crosslink density, Ionic polarizing energy, Orbital hybrid bonding procedure, Effective principal quantum number, Ionicity,  σ-covalency and spatial covalency, forming a Dual Method of the multiple-functional prediction. It could explain quantitatively the chemical phenomena and correlate qualitatively to the universal observations, forming International Ionocovalency Schools.

He improved the Nobel Prize Pauling electro-negativity, in which "the major difficulty is that the attraction for an electron is clearly not expected to be the same for different valencies of an element" (“atom electronegativity”).  Zhang proposed an ionic electronegativity in different valences， and it is therefore encompassed in university textbook

He was elected Member and Chartered Chemist of the Royal Society of Chemist.

Miserable Childhood

Yonghe Zhang was born in a wealthy family. The property was confiscated by CCP. Mother was thus committed suicide. Father's life can not escape the fate repressed. In 1951, when 11 years old Zhang participated in the People's Liberation Army, his father became the "Glorious Army Family Members", and so was rescued. In 1952 pestilence, three sisters no one spared death. 1960 China Famine finally killed his father, from then on he becomes a lonely goose.

Career Dream

After the military demobilization in 1953 he back to Yongdeng High School, serving as the student's president. Unfettered life experience evoked his determined diplomatic career dream. In addition to the Russian language offered by the school, he also taught himself English and Polish. He Wrote a letter in four languages to apply for the Foreign Affairs College. However, an event of ruining his whole life occurred.

Small Insurgent

In high school, Zhang Yonghe led the student protest referring a CPC principal's sex scandal,   so he was designated as the "anti-CPC " and the entire young age experienced suffering physical and mental stress,  being buried and back to life when mining the ore. More serious is lost apply for University political qualifications. However, he did not give up the pursuit of life. When the admission exam, he chose English as the test subjects, which the school had not been opened. He completed within 15 minutes the 1959 English entrance examination almost full marks and admitted to Lanzhou University in the condition of being politically supervised.

Spared Death

Graduated from Lanzhou University in 1965, he was assigned to the Shanghai Petrochemical Research Institute as an engineer. During the Cultural Revolution, when he write on the posters paper two words，“down with”，but on the back of the poster paper printed three words，“Mao Zedong” ，a political investigator found and got it as the evidence, combined with landlord family origin and history of anti-CPC faced the bad luck of being executed, thanks to the good people to hide "incriminating evidence"，spared death.

In 1974 he married the same fate capitalist daughter Wang Rongping. Married 10 years,  the outer suburbs wife, unfortunately, suffering from a brain tumor, baby reared by him alone.

Blip

The end of the Cultural Revolution in 1976, in order to recover the lost years, wiped out a contemptuous life in difficult circumstances, he finished his paper published the ion electronegativity. 1987 elected as a Member of the Royal Society of Chemistry and Chartered Chemists.

Soon, Central Shanghai Municipal Office of Scientific Research convey General Secretary Hu Yaobang "four-point instructions on the care and support of Zhang.

Despite drastic changes. General Secretary Hu Yaobang, unexpectedly deposed. Zhang was alluded to Hu Yaobang "liberalization" route and had to carry the young son and sick wife to the United States.

Came to the USA

In 1988 he came to the United States in exchange for the scholar. In order to get a better medical insurance for his wife, he accepted a government job as an ecology scientist for the City of New York in 1992, but his wife soon died. 20 years in the laboratory, he developed ultra-trace element analysis technology, training technical backbone. Retirement in May 2013.

A Debate with Pauling on Electronegativity

The concept of electronegativity was recognized as a useful ordering principle in chemistry especially since the definition given by Pauling in 1939.  However,  it is unlikely to contribute to an understanding of the chemical reactions involved in the valence change because it is not uniquely defined.  

In 1981 Zhang established the spectroscopic quantum model for the effective nuclear charge and effective principal quantum number Z*= n*(Iz/R)½ and proposed the first ion electronegativity in valence states, quantifying the Pauling’s single-value electronegativity.  Mackay et al. pointed out that the major difficulty in Pauling's electronegativity is that the attraction for an electron is clearly not expected to be the same for different valencies of an element, and they encompassed in their university textbook the Zhang electronegativity in valences. But Pauling was still in the confusion  “A Letter from Linus Pauling” stated: “I must say that I am not able to form a reliable opinion about the value of your work. I note that for a number of the elements your calculated values are close to my values of the electronegativity, and also that for other elements there is a considerable deviation. I suggest that you might discuss some property of the elements, in various compounds, and in different valence states, in order to find out whether or not your values are helpful in understanding the properties.”  Zhang responded with the new research and a second paper,  A scale for strengths of Lewis acid, was published, satisfactorily replied Pauling’s concern, wherein 126 metal ions Lewis acid strengths, in various compounds, and in different valence states, are calculated from the model: Z = z/r2 - 0.77 Xz + 8.0 . The calculation results agree fairly well with the Pearson classification and the previous work.Based on this model, an ionocovalent school formed in France headed by Josik Portier and Lenglet M, and Zhang received hundreds of appreciation letters and cards. A letter from  Nobel Laureate, Henry Taube confirmed: "Electronegativity continue to be a useful concept, and becomes even more useful when it is treated as a function of oxidation state."   ( “Debate on Pauling Electronegativity Confusion”.)

Ionocovalency theory

The new research made Zhang find the ionocovalent duality in hydrogen atom and proposed ionocovalency theory that everything exists in Ionocovalency, the ionic energy harmonized with the covalent environment:

I(Z*)(n*rc-1) = Ze2/r = n*(Iz/R)½ rc-1

which correlates with quantum potential and spectroscopy, in which he revealed new findings on molecular science  ( Science Letter )

Being composed of the ionic function I and the covalent function C, the model describes quantitatively the dual properties of bond strengths, charge density, and ionic potential. Based on the atomic electron configuration of 1s-nf and the various quantum-mechanical built-up dual-parameters, the model formed a Dual Method of the multiple-functional prediction, which has much more versatile and exceptional applications than traditional electronegativity scales and molecular properties.

He unified the old antagonistic qualitative relations of the ionic-versus-covalent dichotomy of bond nature and established a new quantitative ionocovalent continuum scale (Ionocovalency in Molecular Science)  In this scale, the ionic and the covalent are inversely proportional; the ‘pure’ ionic and ‘pure’ covalent bonds could be seen as two extremes of an ionocovalent continuum. And so a covalent bond scale has the ionic bond degree (Ionocovalent Bond Parameters, Functions and Scales).

He correlated ionocovalency with the macro-micro and physical laws. It is derived from the microscopic deduction of quantitative experiments and mathematics and correlated to the macroscopic induction of the universal qualitative observations. Therefore, this interpretation of the survival mechanism of the hydrogen atoms of the source of all things, through the micro-and macro-induction of Ionocovalency model, bound to describe the existence of universal things (Ionocovalency in Universal Philosophy)..

Yonghe Zhang’s Major Works：

* Zhang, Y. Electronegativities from Ionization Energies, J. Mol. Sci, Chinese, 1, 125(1981).

* Zhang, Y. Electronegativities of Elements in the Valence States and Their ...1 Electronegativities of elements in valence states, Inorg. Chem., 1982, 21 (11), pp 3886–3889

* Zhang, Y. Electronegativities of Elements in Valence States and Their ... 2 A scale for strengths of Lewis acids, Inorg. Chem., 1982, 21 (11), pp 3889–3893

* Zhang, Y. A Spectroscopic Quantum Model: 1. Effective Nuclear Charge 2. Effective Principal    Quantum Number J. Am. Huilin Ins. 2012, 4, 1-23

* Zhang, Y. Ionocovalency and Applications 1. Ionocovalency Model and Orbital Hybrid Scales.

   Int. J. Mol. Sci. 2010, 11, 4381-4406. IC-Model Full-Text

* Zhang, Y. Ionocovalency and Applications  2. IC-Lewis acid strengths J. Am. Huilin Ins. 2011, 11,

* Zhang, Y. Ionocovalency and Applications 3. Ionocovalent Crosslink Density J. Am. Huilin Ins

* Zhang, Y. Ionocovalency Theory, J. Am. Huilin. Ins. 2011, 5, 1-11

* Zhang, Y. 离子共价论, J. Am. huilin. Ins. 2011, 5 (B), 1-9

* Zhang, Y. Zhang Ionocovalency Contributions, J. Am. Huilin. Ins. Dec.11, 2010

* Zhang, Y. Universal Ionocovalency, J. Am. Huilin. Ins. 2011, 9, 26

* Zhang, Y. Am.Huilin Inst., Zhang Electronegativity, J. Am. Huilin. Ins Jan.31, 2011

* Zhang, Y. Debate on Pauling Electronegativity's Confusion, J. Am. Huilin. Ins. Nov. 19, 2011