Patent ID: 7656158

Claim:
A sample vessel for NMR measurements, the vessel having a vessel material with a magnetic susceptibility χ 2 and placed in an environment having a magnetic susceptibility χ 1 , the vessel containing a liquid sample having a magnetic susceptibility χ 3 , the vessel comprising: an outer interface that limits the sample vessel with respect to the environment, the outer interface having an outer cylindrical surface shaped as cylinder envelope with an axis of symmetry which is aligned parallel to a z-direction and an outer closing surface that closes the sample vessel at a lower end thereof and which is contiguous to the outer cylindrical surface, wherein, when an external homogeneous magnetic field B 0 parallel to the z-axis is applied, the outer interface causes, due to a jump in susceptibility from χ 1 to χ 2 in the region of the sample volume, a field B z (1) with an average value in the sample volume <B z (1) > and therefore a first relative field change F 1 =(B z (1) −<B z (1) >)/B 0 that, at least in a part of the sample volume, has an absolute value of no less than 0.5·10 −6 ; and an inner interface that limits the sample vessel with respect to a sample volume, the inner interface having an inner cylindrical surface shaped as a cylinder envelope with an axis of symmetry which is aligned parallel to the z-direction and an inner closing surface that closes the sample volume at a lower end thereof and which is contiguous to the inner cylindrical surface, wherein, when an external homogeneous magnetic field B 0 parallel to the z-axis is applied, the inner interface causes, due to a jump in susceptibility from χ 2 to χ 3 in the region of the sample volume, a field B z (2) with an average value in the sample volume <B z (2) > and therefore a second relative field change F 2 =(B z (2) −<B z (2) >)/B 0 that, at least in a part of the sample volume, has an absolute value of no less than 0.5·10 −6 , wherein the first relative field change F 1 and the second relative field change F 2 largely cancel each other out in the sample volume V so that the following applies ∫ V ⁢ ( F ⁢ ⁢ 1 + F ⁢ ⁢ 2 ) 2 ⁢ ⁢ ⅆ V ≤ 0.9 · ∫ V ⁢ ( F ⁢ ⁢ 3 ) 2 ⁢ ⁢ ⅆ V , wherein the inner interface would cause, due to a jump in susceptibility of χ 1 to χ 3 in the region of the sample volume, a field B z (3) with an average value in the sample volume <B z (3) > and therefore a third relative field change F 3 =(B z (3) −<B z (3) >)/B 0 .