User:Tmyh7/sandbox

Tutorial stuff

my sandbox page is at User:tmyh7/sandbox

The tutorial talk page is https://en.wikipedia.org/wiki/User_talk:Tmyh7/talk_page_tutorial

Article Evaluation

History of Spectroscopy

• Is everything in the article relevant to the article topic? Is there anything that distracted you? -- Yes, no distractions
• Is the article neutral? Are there any claims, or frames, that appear heavily biased toward a particular position? -- yes
• Are there viewpoints that are overrepresented, or underrepresented? -- no
• Check a few citations. Do the links work? Does the source support the claims in the article? Yes the citations work and support claims
• Is each fact referenced with an appropriate, reliable reference? Where does the information come from? Are these neutral sources? If biased, is that bias noted? -- yes it is reliable, most citations are from books.
• Is any information out of date? Is anything missing that could be added? -- no out of date info. More things could be added about history after 1900.
• Check out the Talk page of the article. What kinds of conversations, if any, are going on behind the scenes about how to represent this topic? -- They discuss where to put information, in this page or another.
• How is the article rated? Is it a part of any WikiProjects? -- it is a start class article and highly important. yes 3 wikiprojects.
• How does the way Wikipedia discusses this topic differ from the way we've talked about it in class? -- We have not discussed it in class.

History of Spectroscopy Article edit

Collaborated with User:Ab6gc/sandbox

We chose this article because it is pretty bare in terms of history, there is no information past 1899. There also isn't very much information in the history prior too 1899, this could easily be expanded upon. We would like to add more in depth info prior to 1899 and start putting in info for history past 1899. This article is also marked as important and a start class article.

Possible sources to help article

https://pubs.acs.org/doi/abs/10.1021/ed068p631 ---The early history of spectroscopy---Nicholas C. Thomas

https://serc.carleton.edu/NAGTWorkshops/mineralogy/mineral_physics/raman_ir.html#Comp ---Infrared and Raman Spectroscopy ---by Sylvia-Monique Thomas

https://web.archive.org/web/20071027110406/http://www.cem.msu.edu/~reusch/VirtualText/Spectrpy/InfraRed/infrared.htm ---Infrared Spectroscopy

http://web.mit.edu/spectroscopy/history/history-modern.html

https://snews.bnl.gov/popsci/spectroscope.html

Notes from sources

Info from 1900 to present

"a mathematical relationship was developed accounted for these lines in the visible emission spectrum of hydrogen. Subsequently, in 1913, Niels Bohr initiated anew era of spectral interpretation by linking line spectra to the quantum ideas recently proposed by Planck and Einstein. Put simply, Bohr proposed that electrons exist in states of constant energy and only change energy by undergoing a transition from one state to another. During the transition they either absorb or emit an amount of energy that is exactly equal to the energy difference between the two states. This behavior produced the characteristic spectral lines." and "The significance of visible emission spectroscopy as a method to study the transitions of outer electrons in atoms and molecules provided a convenient tool to examine the electronic structure of matter. Like emission spectra, absorption spectra were classified as either continuous or line spectra and were also used to identify elements or study electronic transitions. August Beer. a German Physicist and professor of mathematics the university of Bonn, recognized the relationship between the absorption of light and concentration (17). One of the first instruments to use the absorption of light to determine concentration was the color comparator (18), which relied on Beer's law. The user visually compared the transmitted light from the sample and a standard solution and adjusted the path length until the transmitted light from both solutions appeared to have the same intensity;. Eventually photodetectors replaced the inaccurate human eye, and in the 1930's a new instrument called the colorimeter or spectrophotometer was developed that used a grating or prism to isolate a specific wavelength for absorption and analysis

from The early history of spectroscopy---Nicholas C. Thomas

Notes

---- This source help to start the subsection of early 20th Century (1900-1940's) in the History of Spectroscopy article. This article has no information of spectroscopy history past 1900 so this article helps give more information.

Information about IR Spectroscopy

"The discovery of the IR region of the electromagnetic spectrum was made by Herschel in 1800. Using a glass prism with blackened thermometers, Herschel detected the existence of radiant heat beyond the visible region near the red end of the solar spectrum. However, since Herschel's main interest was astronomy, he did not investigate this phenomenon further, and nearly a century elapsed before interest in the infrared region arose again. In 1882 Abney and Festing obtained IR absorption hands with the presence of certain organic groups in the molecules. Using sodium chloride plates, Julius recorded the spectra of 20 organic compounds and noted that methyl groups absorbed at characteristic wavelengths. By the turn of the century interest in IR spectroscopy &as rapidly growing. Beginning in 1903, W. W. Coblentz conducted a series of measurements over several years, during which time he studied the IR spectra of hundreds of organic and inorganic compounds (24). However, early workers studying IR encountered many experimental problems. They had to design, construct, and calibrate their own instruments and components, and measurements were generally recorded at night to minimize the effect of vibrations on the sensitive instruments. In addition, it took 34 hours to record a single spectrum. Due to the difficulty in measuring IR spectra, chemical applications were very limited until the 1940's." and "During World War II the US. government was interested in producing synthetic rubber by the polymerization of butadiene. This process required the analysis of Ca hydrocarbon isomers for which there was no commonly accepted method of analysis. The government offered support to two industrial research labs to design such an instrument: they were the Shell Development company in California and the Cyanamid Company in Connecticut. Cyanamid convinced the tin Perkin-Elmer optical shop to construct optical elements for a prototype IR. The instrument Perkin-Elmer built was one of the first operating infrared spectrometers, the Model 12. At about the same time the Beckman Company, through a similar arrangement with Shell, developed their Model IR-1 instrument. Once available commercially, these and successive instruments greatly enhanced the popularity of the IR technique, which, with the exception of optical isomers, was able to provide a unique "fingerprint" for any molecule." From The early history of spectroscopy---Nicholas C. Thomas

Notes

--- This source greatly helps to develop my understanding of the first IR spectrometers and the history of why they were initially developed. Also helps information from 1900 to present.

Original History of spectroscopy Draft

Early 20th century (1900-1950)

In 1913, Niels Bohr discovered the emission of spectral lines by observing electrons transitioning from different energy states within an atom. August Beer then observed a relationship between light absorption and concentration and created the color comparator which was later replaced by a more accurate device called the spectrophotometer. In 1937 "E. Lehrer created the first fully-automated spectrometer" to help more accurately measure spectral lines. With the development of more advanced instruments such as photo-detectors scientists were then able to more accurately measure specific wavelength absorption of substances.

IR and Raman Spectroscopy

Many early scientists who studied the IR spectra of compounds had to develop and build their own instruments to be able to record their measurements making it very difficult to get accurate measurements. During World War II the U.S. government contracted different companies to develop a method for the polymerization of butadiene to create rubber, but this could only be done through analysis of Ca hydrocarbon isomers. These contracted companies started developing optical instruments and eventually created the first infrared spectrometers. With the development of these commercial spectrometers Infrared Spectroscopy became a more popular method to determine the "fingerprint" for any molecule. Raman spectroscopy was first observed in 1928 by Sir Chandrasekhara Venkata Raman in liquid substances and also by "Grigory Landsberg and Leonid Mandelstam in crystals". Raman spectroscopy is based on the observation of the raman effect which is defined as "The intensity of the scattered light is dependent on the amount of the polarization potential change". The raman spectrum records light intensity vs. light frequency (wavenumber) and the wavenumber shift is characteristic to each individual compound.

Laser Spectroscopy

The laser was invented in 1960 by spectroscopists who took the concept of its predecessor, the maser, in the visible range of light. Lasers have gone on to significantly advance experimental spectroscopy. The laser light allowed for much higher precision experiments specifically in the uses of studying collisional effects of light as well as being able to accurately tell what each wavelength and frequency of light were, allowing for the invention of things such as laser atomic clocks. Lasers also made spectroscopy with respect to time more accurate by using speeds or decay times of photons at specific wavelengths and frequencies to keep time.

Peer review of Laser Spectroscopy from ab6gc

Mnwfk2 peer evaluation Mnwfk2 (talk) 18:27, 18 March 2018 (UTC)

• The article is neutral, there are no claims that I could see that are biased
• The viewpoints you have focused on are very prevalent to the article, but it would be interesting to look into how laser spectroscopy has impacted different industries and scientific fields.
• References
  • For reference number 2, maybe look at the references they list at the end of the article
  • Try to find articles specifically relating to lasers or laser spectroscopy and put information on how lasers work.
  • searching laser spectroscopy from the library website might get good results!
• Add citations to sources for each sentence, even if an entire paragraph is from the same source
• Better define how lasers can be used in spectroscopy, and why this has made significant improvements to the technique
• The draft looks good so far you guys are doing a great job!!

Responding to peer review

• We could talk about the fields of industry or science that laser spectroscopy effect, but at this point this is just the general introduction of the idea and it will get into that as we expand the article.
• Good idea looking at already existing references.
• We cannot delve too deeply on how lasers work because that information would belong in the Lasers wiki page, but it should be a very brief explanation.
• This article is not about lasers in spectroscopy, laser spectroscopy is a single element in itself. It could possibly be better defined but as it stands it defines it well enough, given the sources we have used thus far. Tmyh7 (talk) 15:37, 23 March 2018 (UTC)