ccdc 操作方法

Searching the Cambridge Crystallographic Database

(CCDC ConQuest)

The Cambridge Crystallographic Database is continually growing database consisting of over 300,000 crystallographically characterized molecules. The database includes many pieces of important information about a published compound, including: •Journal Name (volume, page, year)

•Author’s Names

•Chemical Name and Formula

•Physical Properties (melting point, color)

•Crystal Information

o Space Group

o Unit Cell Parameters (a, b, c, α, β, γ)

o Reduced Cell Parameters

o Molecular Volume

•Known Polymorphs (same sample crystallized in a different way)

•Experimental Detail

o Collection Temperature

o Crystal Density

o R factor (indication of quality of structure)

o Average Sigma (C-C) for bond distances

o Whether or not the structure contains disorder

•Diagrams (ChemDraw and 3D view)

Unlike Scifinder and Beilstein, the CCDC only contains articles with structurally characterized compounds. The major advantage to this database is that you can find structural information (bond lengths, bond angles, molecular geometry, and hydrogen bonding interactions to name a few) quite quickly without having to search through every article published about a certain compound. One obvious disadvantage is that if the compound has not been structurally characterized, it will not be present in the database.

A second disadvantage is that the database in not a web-based database; rather periodic updates (every 3 months) are need to keep the database current.

Many groups on campus have a license for the database. If your group does not have a license, you can use the database in the X-ray Crystallography Lab (S146) during normal operational hours (8-5 daily); though, due to the cost of getting the database, there is a fee for non-licensed users ($57). See either: the director, Victor Young, or the TA, Ben Kucera if you have any questions.

To search the database, first click on the icon “ConQuest1.7” (or whatever version is present in your lab).

The first screen you come to will look like this:

This screen shows you all of the available search options. The following list is a brief description of each function.

•“Draw” is a drawing program

•“Peptide” allows you to specify amino acid linkages

•“Author/Journal” allows you to search for a particular author or in a particular journal

•“Compound Name” allows you to search based on the published name

•“Elements” allows you to specify certain elements to search for

•“Formula” allows you to search based on a specific formula

•“Space Group” allows you to search for a specific space group

•“Unit Cell” allows you to find samples based on the unit cell and reduced cell parameters

•“Z/Density” allows you to search for a particular crystal density or a particular number of molecules in the unit cell

•“Experimental” allows you to search for samples based on experimental data, such as data collection temperature, R factor, and average sigma (C-C) •“All Text” allows you to search based on keywords and phrases

•“Refcode (entry ID)” allows you to search based on the 6 letter CCDC code that each entry has

Each function will now be described in further detail.