A method for generating gaseous molecular ions for analysis by a mass spectrometer or ion mobility spectrometer, comprising: accelerating a sample toward a solid surface (130; 130'; 442; 530; 530'; 730), wherein accelerating said sample comprises driving said sample via a pressure gradient along a tubular opening through which said sample is introduced from an atmospheric pressure regime to a lower pressure regime of a spectrometer, and wherein said sample comprises: (i) an aerosol sample (120; 520; 520') comprising one or more molecular particle clusters; or (ii) a continuous liquid jet sample ; colliding said sample with said solid surface to disintegrate said one or more molecular particle clusters or said continuous liquid jet, thereby forming one or more gaseous molecular ions (140; 140') and neutral molecules (150; 150'); and collecting said gaseous molecular ions (140; 140') and directing said gaseous molecular ions to an analyzer unit ; wherein either: (i) said surface is disposed in an ion funnel type mass spectrometric atmospheric interface, said ion funnel configured to collect said gaseous molecular ions, wherein said surface is a generally spherical surface or a conical surface; or (ii) said surface is disposed between the opening through which said sample is introduced and a skimmer electrode, wherein said surface is a generally spherical surface or a conical surface; or (iii) said surface is a tubular surface of a skimmer electrode. accelerating a sample toward a solid surface (130; 130'; 442; 530; 530'; 730), wherein accelerating said sample comprises driving said sample via a pressure gradient along a tubular opening through which said sample is introduced from an atmospheric pressure regime to a lower pressure regime of a spectrometer, and wherein said sample comprises: (i) an aerosol sample (120; 520; 520') comprising one or more molecular particle clusters; or (ii) a continuous liquid jet sample ; (i) an aerosol sample (120; 520; 520') comprising one or more molecular particle clusters; or (ii) a continuous liquid jet sample ; colliding said sample with said solid surface to disintegrate said one or more molecular particle clusters or said continuous liquid jet, thereby forming one or more gaseous molecular ions (140; 140') and neutral molecules (150; 150'); and collecting said gaseous molecular ions (140; 140') and directing said gaseous molecular ions to an analyzer unit ; wherein either: (i) said surface is disposed in an ion funnel type mass spectrometric atmospheric interface, said ion funnel configured to collect said gaseous molecular ions, wherein said surface is a generally spherical surface or a conical surface; or (ii) said surface is disposed between the opening through which said sample is introduced and a skimmer electrode, wherein said surface is a generally spherical surface or a conical surface; or (iii) said surface is a tubular surface of a skimmer electrode. (i) said surface is disposed in an ion funnel type mass spectrometric atmospheric interface, said ion funnel configured to collect said gaseous molecular ions, wherein said surface is a generally spherical surface or a conical surface; or (ii) said surface is disposed between the opening through which said sample is introduced and a skimmer electrode, wherein said surface is a generally spherical surface or a conical surface; or (iii) said surface is a tubular surface of a skimmer electrode. <EOS>