Pigment Report Assignment

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PIGMENT RESEARCH PROJECT – FINAL REPORT
REEL – RESEARCH EXPERIENCES TO ENHANCE LEARNING
PURPOSE
The final report details the findings of your research project. This information will be used
to assess the scientific knowledge generated by your work and to guide future
implementations of the project. It also serves as an exercise in scientific writing.
ASSIGNMENT
Components of the Report
Your research results should be presented in the format of a scientific paper. It is not
necessary to write in the third person, but the report should be written from an objective
viewpoint (you should not report the results with a bias for one outcome over another).
Use past tense to report results and present tense to discuss them. The report should be
single spaced with bold headings to denote the beginning of each of the following
sections.

Title

Authors

Abstract

Introduction

Experimental

Results

Discussion & Conclusions

Future Directions

Acknowledgements (optional)

References

Your thoughts on the REEL Program
Rough guidelines for each section of the report are given on the following pages. When
preparing your report keep the following points in mind: (a) Each student is responsible for
his or her own report, (b) While the data will be the same for the entire group, each student’s
writing should be his or her own. Figures and Tables may be the same for all students in the
group, the conclusions may also be similar, but the text should be unique. Directly copying
any section of the report (other than figures and tables) from someone else in the group
will be grounds for academic misconduct.
SECTION GUIDELINES
Title
The title should be succinct, yet sufficiently descriptive to alert the reader as to the content
of the project. For example, “Synthesis and Characterization of Ag3(VO4)1–x(PO4)x Pigments”
Authors
In scientific publishing all people who intellectually contribute to a project should be
included as co-authors. List yourself as the first author, followed by the other members of
your group. The last name in the author list should be your peer mentor.
Abstract
This is a short (50-100 words) summary of the goals and findings of the research project.
Introduction
The introduction describes the motivation for the research and describes the state of
knowledge before the research project started. For this paper there should be a ½ to 1 page
background on the pigment(s) you were seeking to replace. This should be followed by
roughly ½ page describing what is known (prior to your research) about the end members of
the solid solution you were exploring, including color and any relevant details you can find
about the crystal structures (crystal system, space group, lattice parameters). You may want
to include other details as you deem appropriate.
Experimental
The experimental part of a paper describes the procedures that were carried out. It should
be sufficiently detailed to allow another researcher to repeat the experiment. In each project
there were four parts to the procedure that need to be described:
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Small scale precipitations in test tubes
Synthesis of samples for characterization
Structural and compositional analysis by X-ray powder diffraction
Optical characterization by UV-Visible diffuse reflectance spectroscopy
Your report should include 1 paragraph describing the results of the small scale
precipitations that led your group to select the end members of your compositional series.
Write net ionic equations for the precipitation reactions that you believe to be responsible
for the precipitation of your end members. Describe the color and consistency of the end
member precipitates that formed. If pH played any role in this process please describe it.
Describe the procedures used for the synthesis of your samples (not the samples
prepared by your group partners). Write a balanced equation for each of your samples. If
you used a solid state synthesis route list the amount of each reactant and the annealing
temperature. If there were multiple cycles of heating give full details. If you prepared
samples by precipitation list full details of the precipitation (solutions used, including
concentrations, volumes, order of mixing, special pH considerations, etc.).
The X-ray diffraction and UV-Visible characterization were more or less the same for
everyone involved. In one paragraph state that the structural and compositional
characterization of the samples was carried out using X-ray powder diffraction (XRPD).
The XRPD data was collected over a given two-theta range (look at your patterns to
determine the 2-theta range) with a Rigaku Miniflex Diffractometer. The optical properties
were characterized by UV-Visible diffuse reflectance spectroscopy using an Ocean Optics
spectrometer equipped with a fiber optic diffuse reflectance probe. Once again here you
should state the wavelength range that was employed.
Results
The results section is where you report the experimental findings, for this research
project the results include:
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The appearance of your samples. Describe the colors of the samples at each stage
of the synthesis. Include the photograph(s) of the samples in your group’s
compositional series as Figure 1.
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The UV-Visible diffuse reflectance spectra. You should show the diffuse
reflectance spectra of all samples in your group’s compositional series as Figure 2.
Comment on whether the onset of absorbance is sharp (giving rise to bright colors)
or smeared out over a wide range of wavelengths (usually leading to brown and
other “muddy” colors).
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If the onset of absorbance is reasonably sharp you will be able to calculate a band
gap for each compound. Create a table, Table 1, which lists the color and band
gap for each compound in your group’s compositional series. If you were able to
successfully form a solid solution plot the band gap (on the y-axis) vs. the
composition (on the x-axis).
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The X-ray powder diffraction patterns provide information about the phase or
phases present in your sample. Include the excel plot of the X-ray powder
diffraction data as Figure 3. From the X-ray patterns you should identify which
phases are present (including unreacted starting material, or undesired side
products) for each compound in your group’s compositional series. Compile this
information in Table 2. The phases in each sample should be identified by the
name and stoichiometry given in the database.
Discussion and Conclusions
Unlike the experimental section where you simply present the experimental facts, this
section is where you comment on what you think they mean. You should address the
following points.
- Did your synthesis work? For each samples did you (a) form a solid solution, (b)
form a 2-phase mixture, (c) form undesired side products, (d) form an
amorphous product, (d) end up with unreacted starting materials? What can
you say about the phase diagram (a figure may be appropriate)? If the synthesis
did not work as planned how might you modify the synthetic procedure to make
it work (a brief discussion and reference to successful syntheses described in the
literature would be appropriate)?
-
What electronic transition is responsible for the color? Is it a charge transfer
transition on the anion or a d-to-d transition on the cation, or both. In either case
it would be appropriate to show a MO diagram as a figure.
Is the color of your compound consistent with the UV-Visible spectrum?
Did your samples form a solid solution? Given the ionic radii of the cations (or
anions) involved is this result expected?
How did the color of your sample change from one end of the compositional
series to the other end. What electronic factors do you think are responsible for
this change.
Would your compound make a good pigment?
Future Directions
Does your system show any promise as a pigment? Are there unanswered questions that
were raised by your work? If you had more time what would be the next step in the
research? Consider these points because I plan to take the take the most interesting
questions raised by this year’s research and use them as starting points for next years
research.
Acknowledgements
This section is optional, but it is appropriate to give credit for anyone else who assisted the
research (either through ideas or action). This could include, but is not limited to, your TA,
someone from another group, Dr. Woodward, a friend or family member.
References
Use numbered endnotes to reference information taken from journal articles, books and
other sources (such as the web). A 10% penalty will automatically be applied to any report
without references. Use the APA style for references as shown below:
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Journal Articles: Author, A. A., Author, B. B., & Author, C. C. (Year). Title of
article. Title of Periodical, volume number (issue number), pages. For example:
Smith, J. C., & Patil, R. K. (2001). Synthesis of Ag3PO4. J. Inorg. Chem. 334(10),
655-672.
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Books: Author, A. A. (Year of publication). Title of work: Capital letter also for
subtitle. Location: Publisher. For example: Woodward, P. M. (2006). General
Chemistry Students: Cheap Labor and Indentured Servitude. Columbus: Ohio State
University Press.
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Electronic Resources: At a minimum, a reference of an Internet source should
provide a document title or description, a date (either the date of publication or
update or the date of retrieval), and an address (in Internet terms, a uniform
resource locator, or URL). Whenever possible, identify the authors of a document
as well. (For more details see http://www.apastyle.org/elecmedia.html)
Your Thoughts on the REEL Program
This section is separate and not graded, but we would be interested to hear your
comments on the following questions:
1.
2.
3.
4.
5.
6.
7.
What aspects of this project did you like?
What aspects of this project did you dislike?
What are your feelings about the peer mentor aspect of the program?
Would you advise future students to enroll in a REEL or a non-REEL Chem 123 course?
What suggestions do you have for improving these labs?
Would you be interested in returning as a peer mentor?
Did this experience alter your views of how research and science in general work? Did
it alter your desire to become involved in research
If you want your comments to be anonymous feel free to give these comments to your TA on
a separate sheet of paper without your name. Your comments are very valuable to us.
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