19F NMR based pH probes: lanthanide(III) complexes with pH-sensitive chemical shifts.
Experimental measurements and theoretical analysis of magnetic properties, structural dynamics and acid-base equilibria for several lanthanide(III) complexes with tetraazacyclododecane derivatives as 19F NMR chemical shift pH probes are presented; pKa values vary between 6.9 and 7.7, with 18 to 40 ppm chemical shift differences between the acidic and basic forms for Ho(III) complexes possessing T1 values of 10 to 30 ms (4.7-9.4 T, 295 K).
Kenwright
Alan M
AM
Department of Chemistry, Durham University, South Road, Durham, UKDH1 3LE.
Kuprov
Ilya
I
De Luca
Elena
E
Parker
David
D
Pandya
Shashi U
SU
Senanayake
P Kanthi
PK
Smith
David G
DG
D000465:Algorithms; D000080027:Cyclams; D005461:Fluorine / Q000737:chemistry*; D006571:Heterocyclic Compounds / Q000737:chemistry; D006845:Hydrocarbons, Fluorinated / Q000138:chemical synthesis / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents / Q000138:chemical synthesis / Q000737:chemistry; D028581:Lanthanoid Series Elements / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D015394:Molecular Structure; D014867:Water / Q000737:chemistry
D000080027:Cyclams; D006571:Heterocyclic Compounds; D006845:Hydrocarbons, Fluorinated; D007202:Indicators and Reagents; D028581:Lanthanoid Series Elements; D014867:Water; D005461:Fluorine; C038072:cyclen