This discussion offers a rich tapestry of personal anecdotes and professional reflections from two scientists, Bill and Harry, regarding their interactions with the legendary Linus Pauling. Bill recounts his early attempts to computationally validate Pauling's bonding theories and their later conversations on topics like nuclear structure, highlighting Pauling's preference for simple, slide-rule-compatible calculations. Harry details his initial, often confrontational, correspondence with Pauling over the utility of ligand field theory versus valence bond theory for explaining chemical properties, culminating in a revealing moment where Pauling's unshakeable self-confidence was laid bare regarding an experimental validation of his own work. A particularly vivid account describes Pauling's impromptu, universally acclaimed lecture at an ACS meeting, where he famously summarized his 1931 hybrid orbital paper as "a pretty good day." The conversation also delves into Pauling's political activism, his Nobel Peace Prize, the controversies surrounding his vitamin C advocacy, and the complex relationship he had with Caltech, ultimately underscoring his unique scientific intuition, immense influence, and enduring, sometimes problematic, legacy.
Insights into Linus Pauling: A Legacy of Science and Self-Confidence
0:04 - Early Inspirations & GVB Methods: Bill, a graduate student, was profoundly influenced by Linus Pauling's "Nature of the Chemical Bond" (1937). He developed "gvb methods" using quantum mechanics to gain an atomic-level understanding of Pauling's bonding ideas, though initial attempts for intermetallic compounds were unsuccessful.
1:30 - Pauling's Distraction Tactics: In a 1962-63 meeting, Bill attempted to present his critical observations of Pauling's theories. However, Pauling skillfully diverted the conversation by discussing various papers and ideas, effectively preventing Bill from raising his specific complaints.
1:52 - Pauling's Encyclopedic Knowledge: Bill notes Pauling's remarkable encyclopedic knowledge and photographic memory, which allowed him to recall vast amounts of scientific information.
2:46 - Caltech's Hesitation & Reconciliation: After Pauling's departure from Caltech around 1964, likely due to his political activities, the faculty initially deliberated whether to invite him back, fearing he might "blast" the institution. Eventually, Caltech established annual birthday celebrations for him, leading to reconciliation and his eventual reinstatement as Professor Emeritus.
4:03 - Shared Interests (Non-Calculational): Bill and Pauling found common ground discussing other scientific concepts, such as Pauling's nuclear structure model (which proposed four isospins) and Bill's work on permutational symmetry. Pauling generally avoided discussions involving complex quantum mechanics calculations that could not be performed with a slide rule.
5:36 - "Not Requiring His Book": Bill, who teaches a Caltech course on "Nature of the Chemical Bond" using Pauling's original course number, recalls Pauling's witty comment upon seeing the course description: it "did not require his book," implying a divergence from Pauling's original text.
6:42 - Harry's Initial Antagonism & Ligand Field Theory: Harry's early interactions with Pauling began around 1960-61. His boss, Carl Bous, was highly critical of Pauling's dismissal of ligand field theory in "Nature of the Chemical Bond," prompting Pauling to write to Harry, criticizing his work in that field.
9:05 - Resonance Structures vs. Diagrams: Following Harry's publication on the ligand field theory of ferrocene, Pauling famously asserted he could explain it better with "over a thousand resonance structures." Harry's sharp retort was, "I can explain it with one diagram."
10:22 - VB for Structure, MO for Spectra: Harry clarifies that while Valence Bond (VB) theory is effective for understanding molecular structure and reactions, Molecular Orbital (MO) theory (specifically Ligand Field Theory for transition metals) is crucial for accurately explaining spectroscopy and colors.
12:44 - Pauling Medal & Friendship: Despite their initial disagreements, Harry and Pauling eventually became close friends. A turning point was when Harry received the Pauling Medal for his work on electron tunneling through proteins, a field outside Pauling's direct expertise, which Pauling acknowledged as "something important."
15:01 - Vindication of Oxyhemoglobin Research: Harry recounts his detailed experimental work to re-measure oxyhemoglobin's magnetic susceptibility. This effort successfully disproved a later study that contradicted Pauling and Corey's 1935 finding that oxyhemoglobin was diamagnetic.
17:00 - "Of Course, I Was Right All Along": When Harry proudly presented Pauling with irrefutable data validating Pauling's original oxyhemoglobin research, Pauling's response was, "Harry, you know why did you waste your time? ... Of course you should have known that I was right all along," a testament to Pauling's unwavering self-confidence.
18:49 - Popularity with Undergraduates: Harry highlights Pauling's immense popularity among undergraduates. An example is a UC San Diego symposium where Pauling's hour-long talk captivated a massive student audience, dwarfing attendance for other clinical presentations.
23:13 - "A Pretty Good Day" - The Hybrid Orbital Story: At an ACS meeting in Denver in the early 1990s, the 90-year-old Pauling gave an impromptu lecture. He famously recounted how, feeling unwell in 1931, he "fiddled around with his orbitals" at home, leading to his groundbreaking discovery of sp, sp2, sp3, dsp2, and d2sp3 hybrid orbitals. He concluded by stating, "You know that was a pretty good day," receiving a seven-minute standing ovation. This anecdote refers to his seminal 1931 hybrid orbital paper.
28:59 - Legacy & Peace Activism: Jenny emphasizes Pauling's enduring scientific legacy, with some of his predictions still being explored today. She quotes the Russell-Einstein Manifesto, co-signed by Pauling, highlighting his commitment to peace, which ironically created difficulties for him at Caltech.
30:38 - Libel Lawsuit Against Buckley: Harry shares the story of Pauling's libel lawsuit against William F. Buckley, who had accused Pauling of being a communist. The case was ultimately dismissed, with the judge noting that as a famous international figure, Pauling had to expect such public criticism.
33:17 - Early Prediction of Xenon Compounds: Bill points out Pauling's prescient insights in the 1930s-40s, where he predicted the existence and octahedral geometry of Xenon compounds like Xenon hexafluoride, which were later experimentally confirmed in the 1960s.
34:20 - Pauling's Dislike for Complex Calculations: The discussion concludes by clarifying that Pauling's aversion to ligand field theory stemmed from its reliance on complex quantum mechanics calculations that were not easily performed with simple tools like a slide rule, and which he viewed as "physical chemistry" rather than "chemistry."
35:32 - Unique Legacy: The speakers conclude by celebrating Linus Pauling as a truly unique figure, being the only individual to receive two unshared Nobel Prizes, whose scientific contributions and human qualities left an indelible mark on the world.