lciemnolonski+log

=**__Chem 767 Log__**= lciemnolonski

__//**9/24/09**//__ Create pages, explore paper topics (MMOF's, film-forming polymers) []

Some MOF's are already on the market (manufactured by BASF, sold at sigma alrich) []
 * //__10/1/09__//**

Typical MOF applications include "hydrogen fuel tanks, drug-delivery devices and CO2 scrubbers" (Paul Voosen, E&E reporter, []) Another application is chemical separation through absorption

Omar Yaghi (University of California, Los Angeles) is a major player in this field.

[]

Papers on ligands found
 * //__10/6/09__//**

__//**10/25/09- 10/29/09**//__ Homework assignment: "Optimised hydrothermal synthesis of multi-dimensional hybrid coordination polymers containing flexible organic ligands," Paz, F. A. A.; Rocha, J.; Klinowski, J.; Trindade, T.; Shi, F.; Mafra, L. Progress in Solid State Chemistry 2005, 33, 113-125. doi:10.1016/j.progsolidstchem.2005.11.033

Abstract: Introduction: Optimization of Hydrothermal Synthesis: Multi-dimensional coordination polymers: Conclusion:
 * Overview of paper content, including review of N-(phosphonomethyl)iminodiacetic acid (H4pmida) as a chelating ligand and the hydrothermal synthesis of various metal-organic frameworks (MOF's). Also contains brief discussion of the magnetic properties of these MOF's.
 * Due to advances in structure control and characterization, the engineering of MOF's is a an intriguing challenge.
 * This kind of engineering research began with Desiraju and Etter on organic crystals. Then, Hoskins and Robson explored multi-dimensional MOF's.
 * The increasing interest in this field is seen through the increasing number of publications on the topic. The overwhelming interest in MOF's is due to their wide variety of applications.
 * This paper focuses on the hydrothermal, high-yield synthesis of multi-dimensional MOF's using dimeric [V2O2(pmida)2]4- units. Also presented is research on a new unit [Ge2(pmida)2(OH)2]2-, which is of great interest because Germanium ions do not exhibit magentism when a magnetic field is applied.
 * Hydrothermal synthesis means that the reaction is carried out in water at a high temperature with at least 1 atm pressure. However, these reaction conditions usually results in poor MOF crystallinity. MOF structures can be determined by single-crystal x-ray crystallography, which requires high-quality crystals.
 * Because of the necessity for high-quality crystals, each MOF reaction needs to be optimized. This can involve adjusting mole ratios, temperature, reaction time and cooling time.
 * This paper reports the optimization of the synthesis of [Cd(BPhDC)(BPE)].(H2O) and [Cd(NDC)(H2O)], where H2BPhDC is biphenyl-4,4'-dicarboxylic acid, BPE is 1,2-bis-(4-pyridyl)ethane, and H2NDC is 2,6-napthalenedicarboxylic acid. Results show the effect of temperature, quenching, and molar ratio on the crystallinity of the final product and synthesis time.
 * Most hydrothermal synthesis optimizations involve the use of chemically robust (usually means it contains benzene rings) bi-dentate organic ligands. The ligand structure is one of the most important factors influencing the framework shape and stability. The use of flexible ligands can lead to isomerism.
 * Multidentate ligands are less desirable because they usually bind to all open metal sites, creating a non-porous mess. Thus, by limiting the number of chelating sites in the ligand, there is more control over the final structure and it's porousity.
 * The H4pmida ligand contains 4 chealting sites, through 2 carboxylic groups, 1 phosphonate group and 1 tertiary amine. This ligand has some interesting flexiblity properties.
 * Hpmida3- was used to create [M2(Hpmida)2(pyr)(H2O)2]2- units, where M2+= Co2+ and Ni2+ and pyr is pyrazine. Magnetic measurements have been done on these materials. Also work was done to create a 1D neutral MOF containing Fe+ metal centers and Hpmida3- as bridging ligands.
 * Crans' initial work on the [V2O2(pmida)2]4- unit led Paz and his group to devise a way to use the unit as a building block in which to construct multi-dimensioal MOF's. It was found that incorporating transition metals and water in the synthesis of these units led to coordination with the P-O bonds of the phosphate group.
 * Further incorporation of 4,4'-bpy led to the formation of 3D MOF's. However one channel of the 3D framework is blocked by guest 4,4'-bpy molecules.
 * Using pyrazine in place of 4,4'-bpy created another new 3D MOF.
 * Increasing the amount of pyrazine in the reaction created yet another new 3D MOF with high yield. Magnetic measurements were also done.
 * X-ray crystallography is the most common means of structure identification in this field, but efforts are being made to use NMR as well. In order to use NMR, the MOF's cannot contain metal ion centers which exhibit magnetism when a magentic field is applied. Thus a relative of the [V2O2(pmida)2]4- unit was created, [Ge2(pmida)2(OH)2]2-, to create NMR-friendly 3D MOF's.
 * The many synthesis methods and variety of organic ligands allow a huge variety of MOF's to be made. Through careful choice of ligands, some control can be executed in the synthesis of these materials. The use of NMR can be a helpful tool when crystal quality is too poor for x-ray crystallography.

Has this assignment been graded? Yes **[Full Marks JCB]**

__//**11/1/2009-11/20/2009**//__ Homework assignment: DONE
 * 1,4-Benzenedicarboxylic acid (Terephthalic Acid), CAS# 100-21-0**

1. specific gravity: 1.510 (experimental); density: 1.451 g/cm3 (predicted) [|ChemSpider] 2. density: 1.522 g/cm3 [|Wikipedia] 3. density: 1.472 g/cm3 [|Wolfram|Alpha] 4. density: 1.510 (assume g/cm3) [|Alfa Aesar] 5. specific gravity: 1.58 [|ChemicalLand21]
 * __Specific Gravity/Density__

1. 300°C [|Chemical Book] 2. 300°C in a sealed tube; sublimes at 402°C (675 K) in air [|Wikipedia] 3. 300°C [|Wolfram|Alpha] 4. 402°C sublimes [|Alfa Aesar] 5. Sublimes at 300° (assume °C), Sax's Dangerous Properties of Industrial Materials (11th Edition) from Merck Index
 * __Melting Point__

1. <0.01 mm Hg (20°C) [|Sigma Aldrich] 2. 1.19 x 10-5 mm Hg (25°C) (calculated) [|OECD SIDS] 3. < 0.01 mm Hg (20°C) [|Acros Organics] 4. 7.35E-07 mm Hg (25°C) (predicted) [|ChemSpider] 5. <0.01 mm Hg (20°C) [|Chemical Book]
 * __Vapor Pressure__

1. 0.0017 g/100mL (0.017 g/L) at 25°C [|Wikipedia] 2. Insoluble in water (0 g/L) [|Acros Organics] 3. Insoluble in cold & hot water (0 g/L) [|Spectrum Chemical MSDS] 4. Insoluble in water (0 g/L), Sax's Dangerous Properties of Industrial Materials (11th Edition) from Merck Index 5. 15 mg/L (0.015 g/L) at 10°C, 19 mg/L (0.019 g/L) at 25°C (measured) [|OECD SIDS]
 * __Solubility in Water__

1. 495°C (923°F) [|Spectrum Chemical MSDS] 2. 925°F (496.1°C) [|Sigma Aldrich] 3. 678°C [|Wolfram|Alpha] 4. 496.1°C (924.98°F) [|Acros Organics] 5. 500°C minimum [|OECD SIDS]
 * __Auto-Ignition Temperature__


 * [Full Marks JCB]

//__11/16/09-12/5/09__ Work on paper on main page //**