PHYSICAL PROPERTIES
 

¹⁸⁷Os NMR spectroscopy is applied on inorganic and organometallic osmium-containing compounds.

A typical standard reference sample is 0.98M OsO₄ in CCl4. The absolute frequencies are 2.282331 MHz for ¹⁸⁷Os and 7.7765400 MHz for ¹⁸⁹Os with respect to 100.00Mhz for TMS. Also see IUPAC recommendations for reporting the NMR chemical shits of all nuclei relative to the ¹H resonance of TMS (02JMR323-156).

Some interesting features of the Os nucleus are:

• ¹⁸⁷Os chemical shifts.
• Long T₁ values.

In osmium-containing compounds the following experiments can be helpful:

• ¹H-decoupled vs ¹H-coupled ¹⁸⁷Os spectrum.
• 2D ¹H-¹⁸⁷Os HSQC experiment ( 85CC65 , 86ICAL47-115 , 89JACS8754 , 90ORG756 ) and HMQC ( 96ORG3124 ) experiments.
• 2D ³¹P-¹⁸⁷Os correlation experiments using phosphorus detection ( 89JACS8754 , 90ORG756 , and 96ORG3124 ).
• Intensity gain ¹H-¹⁸⁷Os factors:

 

NOE	INEPT	Inverse INEPT	HMQC
22.6	43.2	284	12264

Interesting review: B91PRE102.
The Transition Metals NMR: B79HAR195.